Sample records for ash paving demonstration

  1. Sinabung Volcanic Ash Utilization As The Additive for Paving Block Quality A and B (United States)

    Sembiring, I. S.; Hastuty, I. P.


    Paving block is one of the building materials used as the top layer of the road structure besides asphalt and concrete. Paving block is made of mixed materials such as portland cement or other adhesive materials, water and aggregate. In this research, the material used as the additive of cement and concrete is volcanic ash from Mount Sinabung, it is based on the results of the material testing, Sinabung ash contains 74.3% silica (SiO2). The purpose of this research aims to analyze the behavior of the paving blocks quality A and B with and without a mixture of Sinabung ash, to analyze the workability of fresh concrete using Sinabung ash as an additive in concrete, and to compare the test results of paving blocks with and without using Sinabung ash. The samples that we made consist of four variations of the concrete mix to experiment a mixture of normal sample without additive, samples which are mixed with the addition of Sinabung ash 5%, 10%, 15%, 20% and 25% of the volume of concrete/m3. Each variation consists of 10 samples of the concrete with 28 days curing time period. We will do the compressive strength and water absorption test to the samples to determine whether the samples are in accordance with the type needed. According to the test result, paving blocks with Sinabung ash and curing time reach quality A at 0%, 5% and 10% mixture with the compressive strength of each 50.14 MPa, 46.20 MPa and 1.49Mpa, and reach quality B at 15%, 20 %,25% mixture with curing time and 0%, 5%, 10%, 15%, 20% and 25% mixture without curing time. According to the absorption values we got from the test which are 6.66%, 6.73%, 6.88%, 7.03%, 7.09% and 7.16%, the entire sample have average absorption exceeding SNI standardization which is above 6% and reach quality C. Based on compressive strength and absorption data obtained Sinabung ash can’t fully replace cement as the binder because of the low CaO content.

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

    Energy Technology Data Exchange (ETDEWEB)



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

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

    Energy Technology Data Exchange (ETDEWEB)

    Rui Afonso; R. Hurt; I. Kulaots


    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.

  4. Scale-Up and Demonstration of Fly Ash Oxonation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Larry LaBuz; Rui Afonso


    This is the fifth quarterly report under DOE Cooperative Agreement No.: DE-FC26-03NT41730. Due a number of circumstances, mostly associated with subcontractor agreements, the actual beginning of the project was delayed from its original award date of March 5, 2003. DOE's Project Manager was kept informed (verbally) by PPL's Project Manager throughout this period. Because of this delay, this is the fifth quarterly report and it refers to the time period from April-July 2005. (An additional month is included in this quarterly report as we have been in a data analyses mode and wanted to provide new data relative to the previous report). During this period, the project team has been reviewing and analyzing data from the onsite ozonation tests, as well as conducting additional laboratory ash and concrete tests. This report summarizes these activities including some preliminary results. No significant issues or concerns are identified.

  5. Ash-Based Building Panels Production and Demonstration of Aerock Decking Building Product

    Energy Technology Data Exchange (ETDEWEB)

    Alan E. Bland; Jesse Newcomer


    Western Research Institute (WRI) of Laramie, Wyoming and AeRock, LLC of Eagar, Arizona (formerly of Bellevue, Washington) partnered, under sponsorship of the U.S. Department of Energy National Energy Technology Laboratory (U.S. DOE-NETL), to support the development of rapid-setting, ash-based, fiber-incorporated ''green'' building products. Green building materials are a rapidly growing trend in the building and construction industry in the US. A two phase project was implemented wherein Phase I assessed, through chemical and physical testing, ash, ash-based cement and fiber composites exhibiting superior structural performance when applied to the AeRock mixing and extrusion process and involved the conduct of pilot-scale production trials of AeRock products, and wherein Phase II involved the design, construction, and operation of a commercial-scale plant to confirm production issues and to produce panels for performance evaluations. Phase I optimized the composite ingredients including ash-based cement, Class F and Class C DFGD ash, and various fiber reinforcements. Additives, such as retardants and accelerators, were also evaluated as related to extruder performance. The optimized composite from the Phase I effort was characterized by a modulus of rupture (MOR) measured between 1,931 and 2,221 psi flexural strength, comparable to other wood and non-wood building materials. Continuous extrusion of the optimum composite in the AeRock pilot-scale facility produced an excellent product that was assembled into a demonstration for exhibit and durability purposes. Finishes, from plain to marbled, from bright reds to muted earth tones and with various textures, could easily be applied during the mixing and extrusion process. The successful pilot-scale demonstration was in turn used to design the production parameters and extruder dies for a commercial scale demonstration at Ultrapanel Pty, Ltd of Ballarat, Australia under Phase II. The initial

  6. Commercial Demonstration of the Manufactured Aggregate Processing Technology Utilizing Spray Dryer Ash

    Energy Technology Data Exchange (ETDEWEB)

    Milton Wu; Paul Yuran


    Universal Aggregates LLC (UA) was awarded a cost sharing Co-operative Agreement from the Department of Energy (DOE) through the Power Plant Improvement Initiative Program (PPII) to design, construct and operate a lightweight aggregate manufacturing plant at the Birchwood Power Facility in King George, Virginia in October 2001. The Agreement was signed in November 2002. The installation and start-up expenses for the Birchwood Aggregate Facility are $19.5 million. The DOE share is $7.2 million (37%) and the UA share is $12.3 million (63%). The original project team consists of UA, SynAggs, LLC, CONSOL Energy Inc. and P. J. Dick, Inc. Using 115,000 ton per year of spray dryer ash (SDA), a dry FGD by-product from the power station, UA will produce 167,000 tons of manufactured lightweight aggregate for use in production of concrete masonry units (CMU). Manufacturing aggregate from FGD by-products can provide an economical high-volume use and substantially expand market for FGD by-products. Most of the FGD by-products are currently disposed of in landfills. Construction of the Birchwood Aggregate Facility was completed in March 2004. Operation startup was begun in April 2004. Plant Integration was initiated in December 2004. Integration includes mixing, extrusion, curing, crushing and screening. Lightweight aggregates with proper size gradation and bulk density were produced from the manufacturing aggregate plant and loaded on a stockpile for shipment. The shipped aggregates were used in a commercial block plant for CMU production. However, most of the production was made at low capacity factors and for a relatively short time in 2005. Several areas were identified as important factors to improve plant capacity and availability. Equipment and process control modifications and curing vessel clean up were made to improve plant operation in the first half of 2006. About 3,000 tons of crushed aggregate was produced in August 2006. UA is continuing to work to improve plant

  7. Pilot Demonstration of Technology for the Production of High Value Materials from the Ultra-Fine (PM 2.5) Fraction of Coal Combustion Ash

    Energy Technology Data Exchange (ETDEWEB)

    T.L. Robl; J.G. Groppo; Robert Rathebone


    Work on the project focused on the determination of the hydraulic classification characteristics of the Coleman and Mill Creek ashes. The work utilized the hydraulic classifier developed earlier in the project. Testing included total yield, recovery of <5 {micro}m ash diameter particles and LOI partitioning as functions of dispersant dosage and type, retention time and superficial velocity. Yields as high as 21% with recoveries of up to 2/3 of the <5 {micro}m ash fractions were achieved. Mean particle size (D{sub 50}) of varied from 3.7 to 10 {micro}m. The ashes were tested for there pozzolanic activity in mortars as measured by strength activity index using ASTM criteria. Additional testing included air entrainment reagent demand and water requirements. The classified products all performed well, demonstrating excellent early strength development in the mortars. Some increased air entrainment demand was noted. The conceptual design of a process demonstration unit PDU was also completed. A flexible, trailer-mounted field unit is envisioned.

  8. Pilot Demonstration of Technology for the Production of High Value Materials from the Ultra-Fine (PM2.5) Fraction of Coal Combustion Ash

    Energy Technology Data Exchange (ETDEWEB)

    T. L. Robl; J. G. Groppo; R. Rathbone; B. Marrs; R. Jewell


    The overall objective of this research was to determine the feasibility of recovering a very fine fraction of fly ash, that is 5 microns in diameter or less and examining the characteristics of these materials in new or at least less traditional applications. These applications included as a polymer filler or as a 'super' pozzolanic concrete additive. As part of the effort the ash from 6 power plants was investigated and characterized. This work included collection from ESP Hoppers and ponds. The ash was thoroughly characterized chemically and physically. Froth flotation was used to reduce the carbon and testing showed that flotation could effectively reduce carbon to acceptable levels (i.e. 0.5% LOI) for most of the substrates tested. in order to enable eventual use as fillers. Hydraulic classification was used in the separation of the fine ash from the coarse ash. Hydraulic classification requires the ash to be dispersed to be effective and a range of dispersants were tested for adsorption as well as sedimentation rate. A wide range of dosages were required (0.3 to 10 g/kg). In general the ponded ash required less dispersant. A model was developed for hydraulic classification. A pilot-scale hydraulic classifier was also designed and operated for the project. Product yields of up to 21% of feed solids were achieved with recoveries of <5 {micro}m particles as high as 64%. Mean particle sizes (D{sub 50}) of the ultra fine ash (UFA) products varied from 3.7 to 10 {micro}m. A patent was filed on the classifier design. A conceptual design of a Process Demonstration Unit (PDU) with a feed rate of 2 tons of raw ash feed per hour was also completed. Pozzolanic activity was determined for the UFA ashes in mortars. In general the overall strength index was excellent with values of 90% achieved in 3 days and {approx}100% in 7 days. Three types of thermoplastic polymers were evaluated with the UFA as a filler: high density polyethylene, thermoplastic elastomer and

  9. 14 CFR 139.305 - Paved areas. (United States)


    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Paved areas. 139.305 Section 139.305... Operations § 139.305 Paved areas. (a) In a manner authorized by the Administrator, each certificate holder... area on the airport that is available for air carrier use as follows: (1) The pavement edges must...

  10. Parallel paving: An algorithm for generating distributed, adaptive, all-quadrilateral meshes on parallel computers

    Energy Technology Data Exchange (ETDEWEB)

    Lober, R.R.; Tautges, T.J.; Vaughan, C.T.


    Paving is an automated mesh generation algorithm which produces all-quadrilateral elements. It can additionally generate these elements in varying sizes such that the resulting mesh adapts to a function distribution, such as an error function. While powerful, conventional paving is a very serial algorithm in its operation. Parallel paving is the extension of serial paving into parallel environments to perform the same meshing functions as conventional paving only on distributed, discretized models. This extension allows large, adaptive, parallel finite element simulations to take advantage of paving`s meshing capabilities for h-remap remeshing. A significantly modified version of the CUBIT mesh generation code has been developed to host the parallel paving algorithm and demonstrate its capabilities on both two dimensional and three dimensional surface geometries and compare the resulting parallel produced meshes to conventionally paved meshes for mesh quality and algorithm performance. Sandia`s {open_quotes}tiling{close_quotes} dynamic load balancing code has also been extended to work with the paving algorithm to retain parallel efficiency as subdomains undergo iterative mesh refinement.

  11. Demonstration of Tar Removal from Paving Equipment and Ground Vehicles (United States)


    difficult job . Red River Army Depot has about 25 vehicles for refurbishing. Other equipment can also be recovered if a convenient solvent and process...solvents including ethyl lactate , dibasic esters, and X-Force were tested with little success. An aqueous solution formulated with

  12. Optimisation of the outburning of ash in grate-fired boilers by means of IR-sensors. Demonstration of the applicability of the method; Optimering av askutbraenning vid rosteldade anlaeggningar med hjaelp av IR-sensorer. Demonstration av teknikens tillaempbarhet

    Energy Technology Data Exchange (ETDEWEB)

    Rudling, L. [TPS Termiska Processer AB, Nykoeping (Sweden)


    The objective of the project was to demonstrate if it is possible by means of a continuous measurement of the fuel-bed temperature along the grate with infrared pyrometers, to optimise the burnout of the ash on the grate by controlling the air-supply. The tests were carried out at a refuse-fuel grate-fired boiler at Hoegdalen, Stockholm. To monitor the temperature of the fuel-bed, 5 pyrometers were installed. The signals from the pyrometers were connected to a PLC, by which the air dampers for the air-supply of the grate could be controlled. To avoiding 'long fire' with bad burnout the distribution of the air was changed when an increase in temperature was detected in the final burnout zone of the grate Results: * By using a slim encapsulation of the infrared sensor, it was possible to obtain such small dimensions of the pyrometer that it could be installed in the fin-wall between the water tubes., * By choosing a suitable installation point for the pyrometer and a good control of the flow and quality of the rinsing air it was possible to obtain a high availability for the pyrometers., * When an increase of the bed-temperature in the last roller zone, from the 500-600 deg C to the 600-700 deg C was detected, the amount of unburned residue in the ash increased from 2-5 % to 5-10 %. By monitoring the temperature of the fuel-bed in the burnout zone of the grate by means of IR-pyrometry, it was possible to indicate operation conditions with a poor burnout. Tests carried out with automatic control of the air supply to the burnout zone based on measured bed temperatures by IR-pyrometry were carried out. The distribution of the burnout air was performed in a manner that when an increase in bed temperature in the burnout zone was detected the amount of air to the last zone was increased and vice versa. During these tests the amount of unburned matter in the ash removed from the grate was 3.5 %, which shall be compared to 4.3 % which was obtained with manual


    Energy Technology Data Exchange (ETDEWEB)

    T.L. Robl; K.R. Henke; J.G. Groppo


    Broad range dispersants, including naphthalene sulfonate-formaldehyde condensates (NSF) and polycarboxylate based products, were tested on both wet and dry fly ash samples from the LG&E Energy Corp. plants in the study. Tests included both total adsorption and measurement of sedimentation rate via time density relationships. A wide range of dosages were required, ranging from 0.3 to 10 g/kg. In general the ponded ash required less dispersant. Leaching tests of 5% ash solutions by weight revealed a wide range of soluble salts to be present in the ash, and found a relationship between calcium ion concentration and dispersant dosage requirement. Other parameters measured included SO{sub 4}, Cl, F, NO{sub 3}, PO{sub 4}, Al, Ca, Mg, K, Na and alkalinity. An assessment was made of the available software to digitally model the overall process circuit. No prefabricated digital model was found for hydraulic classification or froth flotation. Work focused on building a model for hydraulic classification in an Excel spread sheet based on Stokes Law. A pilot plant scale hydraulic classifier was fabricated and operated. The performance of the hydraulic classifier was found to be forecastable within reasonable bounds, and work to improve both are ongoing.

  14. Paving the Way for Apollo 11

    CERN Document Server

    Harland, David M


    In 'Paving the Way for Apollo 11' David Harland explains the lure of the Moon to classical philosophers, astronomers, and geologists, and how NASA set out to investigate the Moon in preparation for a manned lunar landing mission. It focuses particularly on the Lunar Orbiter and Surveyor missions.

  15. Global Optimization by Energy Landscape Paving

    CERN Document Server

    Wille, L T; Wille, Luc T.


    We introduce a novel heuristic global optimization method, energy landscape paving (ELP), which combines core ideas from energy surface deformation and tabu search. In appropriate limits, ELP reduces to existing techniques. The approach is very general and flexible and is illustrated here on two protein folding problems. For these examples, the technique gives faster convergence to the global minimum than previous approaches.

  16. The Road to Success in Africa is Paved in Asphalt: Transportation Infrastructure Development in Emerging Economies as a Way to Achieve National Strategic Policy Objectives (United States)


    trade, and communication. These case studies provide examples and precedents of the challenges and benefits that resulted and will be studied in...were paved over their entire length. 10 Around 300 B.C. the Romans discovered sandy volcanic ash near Mount Vesuvius . They combined this ash with...of the requirements for the degree MASTER OF MILITARY ART AND SCIENCE Strategic Studies by BRENDAN JOHN McEVOY, MAJ, US ARMY B.A

  17. Pilot Demonstration of Technology fo the Production of High Value Materials from the Ultra-Fine (PM 2.5) Fraction of Coal Combustion Ash

    Energy Technology Data Exchange (ETDEWEB)

    T.L. Robl; J.G. Groppo; K.R. Henke


    Work on the project primarily focused on the design and testing of different hydraulic classifier configurations. A four cell, open channel, cross flow classifier with and without weirs separating the cells was evaluated. Drawbacks to this configuration included thick sediment compression zones and relatively low throughput. The configuration was redesigned with inclined lamellae plates, to increase sedimentation area and decreased sediment compression zone thickness. This configuration resulted in greater throughput for any given product grade and enhanced product recovery. A digital model of a hydraulic classifier was also constructed based upon Stokes law and the configurations of the tests units. When calibrated with the size of the ash used in the tests, it produced a reasonable approximation of the size, yield and recovery of the actual product. The digital model will be useful to generate test data, at least on a relative basis, of conditions that are hard to generate in the laboratory or at larger scale. Test work on the dispersant adsorption capacity, settling tests and leaching test were also conducted on materials collected from the Coleman power station pond.

  18. Paving materials for heat island mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Pomerantz, M.; Akbari, H.; Chen, A.; Taha, H. [Lawrence Berkeley National Lab., CA (United States); Rosenfeld, A.H. [Dept. of Energy, Washington, DC (United States)


    This report summarizes paving materials suitable for urban streets, driveways, parking lots and walkways. The authors evaluate materials for their abilities to reflect sunlight, which will reduce their temperatures. This in turn reduces the excess air temperature of cities (the heat island effect). The report presents the compositions of the materials, their suitability for particular applications, and their approximate costs (in 1996). Both new and resurfacing are described. They conclude that, although light-colored materials may be more expensive than conventional black materials, a thin layer of light-colored pavement may produce energy savings and smog reductions whose long-term worth is greater than the extra cost.

  19. Volcanic ash impacts on critical infrastructure (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.


    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

  20. Evaluation and demonstration of remediation alternatives for historical mine waste using ash and alkaline by products; Utvaerdering och demonstration av efterbehandlingsalternativ foer historiskt gruvavfall med aska och alkaliska restprodukter

    Energy Technology Data Exchange (ETDEWEB)

    Baeckstroem, Mattias; Sartz, Lotta; Karlsson, Stefan (MTM, Man-Technology-Envionrment, Oerebro Univ., 701 82 Oerebro (Sweden))


    The results clearly show that the use of alkaline by products can significantly reduce the leakage of trace metals from historical acid mine waste. Under ideal conditions (laboratory experiments) pH increase significantly and the trace metal concentrations decrease with around 99% compared to the untreated reference. During more realistic conditions (pilot scale) the same increase in pH was not obtained and thus the decrease in trace metal concentrations was not as great. In the stabilisation experiments pH was between 5.8 and 6.8 while the trace metal reduction was around 96-99%. In the filter experiments a median pH between 4 (aged ash) and 10 (lime kiln dust) was obtained after the alkaline section. Average metal reduction is around 95% for cadmium, copper and lead while it is slightly lower for zinc (85%). In summary it is indicated that hydroxide dominated materials work best in aerated environments while carbonate dominated materials work best in reducing environments. In summary it can be concluded that the use of alkaline by products to neutralise acidic mine waste and acid mine drainage from historical mine sites give rise to both environmental and economical benefits and should therefore be encouraged as a sustainable remediation method

  1. Study on Producing Heavy Paving Asphalt

    Institute of Scientific and Technical Information of China (English)

    Liu Daosheng; Gao Zhirong; Huo Kaifu; Liao Kejian


    The highly viscous crude oil from Shuguang No. 1 zone of Liaohe oilfield features high density,high viscosity and low wax content. It contains no gasoline fraction and its diesel oil fraction yield is only 7.19%, which belongs to the low sulfur naphthenic stocks crude oil. Its heavy fraction is not suited for producing lubricating oil. Its heavy oil, which contains more resins and asphaltenes and less wax, is not an ideal feedstock for catalytic cracking, but is the ideal raw material for producing high-grade paving asphalt.Now this highly viscous crude oil is used as fuel oil after being emulsified in Liaohe oilfield, but its viscosity is so high that it cannot be atomized uniformly and burned completely, resulting not only in waste of oil resource but also in reduction of economical benefit. To make full use of this oil resource and alleviate the shortfall of high grade paving asphalt in China, various brands of asphalt meeting Q/SHR003-1998and ESSO specifications were developed by blending vacuum residue of the said oil and a blending component which are rich in aromatics and deficient in wax. The impact of blending component on properties of blended asphalt has been investigated and road performances of these blended asphalts were studied. The laboratory test results show that the blended asphalts have good road performance and antiaging property.

  2. Leachates from wood ash - effects of storage on soil; Lakvatten fraan skogsbraensleaska - markpaaverkan av lagring

    Energy Technology Data Exchange (ETDEWEB)

    Valeur, Inger; Thelin, Gunnar (EkoBalans FenixAB, Lund (Sweden))


    In this study we monitored leachate from wood ash stored in a pile in an outdoor environment during six months. Our aim was to contribute with knowledge about leaching behavior and risks connected to storages of wood ash, and more generally leaching from piles affected by various weather conditions. Impacts on soil from storage of wood ash was also included in the study as well as different transport scenarios for recycling wood ash to the forest. Bioenergy output from Swedish forests has more than doubled the last 10 years and as nutrient rich parts as needles and branches (grot) is also taken out, the nutrient export from the forest site has increased by a factor of three to five. To counteract depletion of nutrients in forest soils, wood ash is returned to the forest. Apart from nitrogen, wood ash contains all the nutrients and trace elements that were in the wood before combustion. The wood ash must be hardened before spreading to make it less reactive. The ash self hardens when stored in an outdoor environment for 3 to 6 months and according to the waste act this should be done on a paved area. However, wood ash which is meant to be recycled to the forest has naturally very low amounts of polluting elements and shall also fulfill limit values, set up by the Swedish Forest Agency. As it is so that the storage is during a limited period of time and the ash shall be transported, not only to one place but too several smaller areas, this has given rise to the thought of storing the ash closer to the spreading area. However, the ash would then probably be stored in a non paved area, as the number of paved areas in forests is scarce. If storage close to the spreading area could be done, the distance for transports connected to recycling the ash would presumably be decrease by a factor of two or three. To get permission to store ash on a non paved area, there must be enough data available which can ensure that there are no environmental risks associated to the storage

  3. 40 CFR 52.2054 - Control of asphalt paving material. (United States)


    ... 40 Protection of Environment 4 2010-07-01 2010-07-01 false Control of asphalt paving material. 52... asphalt paving material. (a) Notwithstanding any provisions to the contrary in the Pennsylvania Implementation Plan, the Pennsylvania Department of Transportation shall restrict the annual usage of asphalts...

  4. Rapid toxicity screening of gasification ashes. (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


    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=0.05IC50, 24hIC50, 24hashes generated in gasification plants every day. Subsequently, appropriate disposal methods can be recommended for each toxicity category.

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

    Energy Technology Data Exchange (ETDEWEB)



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

  6. Properties and Leachability of Self-Compacting Concrete Incorporated with Fly Ash and Bottom Ash (United States)

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


    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.


    Asphalt Inst., College Park, MD.



    Directory of Open Access Journals (Sweden)

    İsa YÜKSEL


    Full Text Available This paper presents results of an experimental study about partial substitution of granulated blast-furnace slag (GBFS as fine aggregate in production of concrete paving blocks and kerbs. GBFS is replaced sand for different GBFS/sand ratios in concrete during production of kerb and paving block specimens. Some tests orienting towards strength and durability were applied on these specimens including control specimens that are produced with normal concrete. Then, the results of tested properties of GBFS-replaced specimens and control specimens were compared. GBFS decreases the compressive strength of paving blocks and kerbs according to the results. However, some durability properties which are more important than strength for these elements are improved with GBFS replacement. The most improved property was abrasion resistance. It is concluded that it is feasible to use GBFS in paving block and kerb production with an optimum replacement ratio for these specimens.

  9. PAVE PAWS Radiation Decays Exponentially in Lossy Materials (United States)


    types of pulses that PAVE PAWS cannot produce. This executive summary will also sketch answers to questions asked during my talk. This report’s section after the transparencies will substantiate the executive summary.

  10. Simplified Pavement Design for LPAs: Introduction to PaveXpress



    Simplified Pavement Design for LPA's; An introduction to and use of PaveXpress, a simplified, free, web-based pavement design scoping tool for roadway and parking lot pavements. The system was developed by Pavia Systems in partnership with the National Asphalt Pavement Association. PaveXpress creates technical sound pavement structural designs for flexible and rigid pavements based on widely accepted industry standards from the Association of State Highway Officials (AASHTO). The simplified p...

  11. [Ash Meadows Purchase Proposal (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...

  12. Fusion characteristics of volcanic ash relevant to aviation hazards (United States)

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


    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.

  13. Disposal of fluidized bed combustion ash in an underground mine to control acid mine drainage and subsidence - phase II - small scale field demonstration. Topical report, December 1, 1996--February 28, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Ziemkiewicz, P.F.; Head, W.J.; Gray, D.D.; Siriwardane, H.J.; Sack, W.A.


    It has been proposed that a mix made from fly and bottom ash from atmospheric pressure fluidized bed coal combusters (FBC ash), water, and stabilizers be injected from the surface into abandoned room and pillar coal mines through boreholes. Besides ash disposal, this process would prevent subsidence and acid mine drainage. Such a mix (called `grout`) needs to be an adequately stable and flowable suspension for it to spread and cover large areas in the mine. This is necessary as the drilling of the boreholes will be an expensive operation and the number such holes should be minimized. Addition of bentonite was found to be needed for this purpose. A suitable grout mix was tested rheologically to determine its fluid flow properties. Finding little published information on such materials, tests were performed using a commercial rotational viscometer with a T-bar rotor and a stand which produced a helical rotor path. Existing mixer viscometer test methods were modified and adapted to convert the measurements of torque vs. angular speed to the material properties appearing in several non-Newtonian constitutive equations. Yield stress was measured by an independent test called the vane method. The rheological behavior was a close fit to the Bingham fluid model. Bleed tests were conducted to ascertain the stability of the mixtures. Spread tests were conducted to compare the flowability of various mixes. Using the flow parameters determined in the laboratory, numerical simulations of grout flow were performed and compared with the results of scale model and field tests. A field injection of this grout was performed at the Fairfax mines in Preston county, W.V.. The observations there proved that this FBC ash grout flows as desired, is a very economical way of disposing the environmentally menacing ash, while also preventing the subsidence and acid mine drainage of the mines.

  14. Directional Tactile Pavings in a Universal Design Perspective. (United States)

    Deichmann, Jacob


    The topic of the presentation is the directional tactile pavings or tactile guidelines that are used by blind and visually impaired people for orientation, in this presentation primarily in the street environment. The focus is the difference between so-called natural and artificial tactile pavings, how they can and should be used, and how the tactile guidelines can be understood as devices of Universal Design. It is discussed whether guidelines based on foreign research can be transferred to the Danish context without additional Danish research. The tests that are known to have been made in Denmark have generally been conducted with a very low number of participants. A secondary focus is the architectural qualities of the tactile pavings, which is a subject for discussion among landscape architects in the Danish context.

  15. Fly ash carbon passivation (United States)

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


    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.

  16. PAVES: A Presentation Strategy for Beginning Presenters in Inclusive Environments (United States)

    Combes, Bertina H.; Walker, Michelle; Harrell, Pamela Esprivalo; Tyler-Wood, Tandra


    Public speaking will continue to be an unsettling experience for some students, including those with disabilities. Experts have suggested several reasons for fearing public speaking; adequate preparation and practice can alleviate most of them. Using the PAVES (Posture, Attitude, Voice, Eye Contact, Smile) strategy described in this article can…

  17. Inhalation and dermal exposure among asphalt paving workers. (United States)

    McClean, M D; Rinehart, R D; Ngo, L; Eisen, E A; Kelsey, K T; Herrick, R F


    The primary objective of this study was to identify determinants of inhalation and dermal exposure to polycyclic aromatic compounds (PACs) among asphalt paving workers. The study population included three groups of highway construction workers: 20 asphalt paving workers, as well as 12 millers and 6 roadside construction workers who did not work with hot-mix asphalt. During multiple consecutive work shifts, personal air samples were collected from each worker's breathing zone using a Teflon filter and cassette holder connected in series with an XAD-2 sorbent tube, while dermal patch samples were collected from the underside of each worker's wrist. All exposure samples were analyzed for PACs, pyrene and benzo[a]pyrene. Inhalation and dermal PAC exposures were highest among asphalt paving workers. Among paving workers, inhalation and dermal PAC exposures varied significantly by task, crew, recycled asphalt product (RAP) and work rate (inhalation only). Asphalt mix containing high RAP was associated with a 5-fold increase in inhalation PAC exposures and a 2-fold increase in dermal PAC exposure, compared with low RAP mix. The inhalation PAC exposures were consistent with the workers' proximity to the primary source of asphalt fume (paver operators > screedmen > rakers > roller operators), such that the adjusted mean exposures among paver operators (5.0 microg/m3, low RAP; 24 microg/m3, high RAP) were 12 times higher than among roller operators (0.4 microg/m3, low RAP; 2.0 microg/m3, high RAP). The dermal PAC exposures were consistent with the degree to which the workers have actual contact with asphalt-contaminated surfaces (rakers > screedmen > paver operators > roller operators), such that the adjusted mean exposures among rakers (175 ng/cm2, low RAP; 417 ng/cm2, high RAP) were approximately 6 times higher than among roller operators (27 ng/cm2, low RAP; 65 ng/cm2, high RAP). Paving task, RAP content and crew were also found to be significant determinants of

  18. Shedding of ash deposits

    DEFF Research Database (Denmark)

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


    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...

  19. Paving asphalt products exhibit a lack of carcinogenic and mutagenic activity. (United States)

    Goyak, Katy O; McKee, Richard H; Minsavage, Gary D; McGowan, Claude; Daughtrey, Wayne C; Freeman, James J


    A paving asphalt and a vacuum residuum (derived from crude oil by atmospheric and subsequent vacuum distillation and used as a blend stock for asphalt) were tested in skin carcinogenesis assays in mice and in optimized Ames assays for mutagenic activity. In the skin cancer tests, each substance was applied twice weekly for 104 weeks to the clipped backs of groups of 50 male C3H mice. Neither the paving asphalt nor the vacuum residuum (30% weight/volume and 75% weight/weight in US Pharmacopeia mineral oil, respectively) produced any tumors. The positive control benzo[a]pyrene (0.05% w/v in toluene) induced tumors in 46 of 50 mice, demonstrating the effectiveness of the test method. Salmonella typhimurium tester strain TA98 was used in the optimized Ames assay to evaluate mutagenic potential. Dimethylsulfoxide (DMSO) extractions of the substances were not mutagenic when tested up to toxic limits. Thus, under the conditions of these studies, neither the paving asphalt nor the vacuum residuum was carcinogenic or mutagenic.

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

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Lars E-mail:


    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

  1. Trace elements in coal ash (United States)

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


    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.

  2. Coprocessing Yanzhou coal with petroleum resid for preparing paving asphalt

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z.; Li, Y.; Yang, J.; Liu, Z.; Chi, H. [Chinese Academy of Sciences, Taiyuan (China). State Key Laboratory of Coal Conversion


    Coprocessing Yanzhou coal with five types of petroleum resid for preparing high grade paving asphalt (HGPA) was investigated. The asphalt obtained was evaluated by 3 indexes: penetration, softening point and ductility. The thin layer chromatography (TLC) and NMR were used to characterise the asphalt. The results show that the properties of resid are crucial for the quality of asphalt. Under the experimental conditions, the resid with the lowest H/C ratio, highest aromatics content and shortest aliphatic side-chain produced asphalt with required quality for high grade paving asphalt used in China. Asphalt yield increased with H{sub 2} pressure and the quality of asphalt decreased with coal to resid ratio. 15 refs., 1 fig., 8 tabs.

  3. Brick Paving Systems in Expeditionary Environments: Field Testing (United States)


    comparable structural characteristics to typical hot-mix asphalt (HMA) or portland cement concrete (PCC) pavements. Brick-paved roads are classified as...bricks were cast in a wood mold and fired in a kiln . This type of process and brick appearance likely are indicative of the type of bricks used in more...included spreading the material to a uniform 12-in. depth at a nearby preparatory site, mixing the material with a rotary mixer, adjusting the

  4. Submicron particle monitoring of paving and related road construction operations. (United States)

    Freund, Alice; Zuckerman, Norman; Baum, Lisa; Milek, Debra


    This study identified activities and sources that contribute to ultrafine and other submicron particle exposure that could trigger respiratory symptoms in highway repair workers. Submicron particle monitoring was conducted for paving, milling, and pothole repair operations in a major metropolitan area where several highway repair workers were identified as symptomatic for respiratory illness following exposures at the 2001 World Trade Center disaster site. Exposure assessments were conducted for eight trades involved in road construction using a TSI P-Trak portable condensation particle counter. Direct readings near the workers' breathing zones and observations of activities and potential sources were logged on 7 days on 27 workers using four different models of pavers and two types of millers. Average worker exposure levels ranged from 2 to 3 times background during paving and from 1 to 4 times background during milling. During asphalt paving, average personal exposures to submicron particulates were 25,000-60,000, 28,000-70,000, and 23,000-37,000 particles/ cm(3) for paver operators, screed operators, and rakers, respectively. Average personal exposures during milling were 19,000-111,000, 28,000-81,000, and 19,000 particles/cm(3) for the large miller operators, miller screed operators, and raker, respectively. Personal peak exposures were measured up to 467,000 and 455,000 particles/cm(3) in paving and milling, respectively. Several sources of submicron particles were identified. These included the diesel and electric fired screed heaters; engine exhaust from diesel powered construction vehicles passing by or idling; raking, dumping, and paving of asphalt; exhaust from the hotbox heater; pavement dust or fumes from milling operations, especially when the large miller started and stopped; and secondhand cigarette smoke. To reduce the potential for health effects in workers, over 40 recommendations were made to control exposures, including improved maintenance of

  5. Modified-sulfur cements for use in concretes, flexible pavings, coatings, and grouts (United States)

    McBee, W. C.; Sullivan, T. A.; Jong, B. W.


    A family of modified-sulfur cements was developed for the preparation of construction materials with improved properties. Various types of sulfur cements were prepared by reacting sulfur with mixtures of dicyclopentadiene and oligomers of cyclopentadiene. Durable cements were prepared with structural characteristics ranging from rigid to flexible. These cements were used to prepare corrosion-resistant materials for use in a wide variety of industrial applications where resistance to acidic and salt conditions is needed. These materials were prepared as rigid concretes, flexible pavings, spray coatings, and grouts. Production of modified-sulfur cements in a commercial-size plant was demonstrated.

  6. Melting and Sintering of Ashes

    DEFF Research Database (Denmark)

    Hansen, Lone Aslaug


    obtained during coal/straw co-firing, substantive sintering strength was observed to build up in the ashes below the melting onset. The strength obtained was thus assumed to be due to viscous flow sintering, and the sintering onset was for the four ashes investigated simultaneous to a calculated ash......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...

  7. TORBED process reactor technology for asphalt paving recycle

    Energy Technology Data Exchange (ETDEWEB)

    Wellwood, G. A. [Torftech Limited, Reading (United Kingdom); Laughlin, R. G. [Torftech Canada Inc., Mississauga, ON (Canada)


    Fundamental principles underlying the TORBED reactor technologies are reviewed. Advantages, limitations, and the experience gained in applying the reactor to a range of material processing needs, particularly reprocessing asphalt paving waste, are discussed. The TORBED reactor consists of a compact shallow packed bed of particles suspended above an annular ring of stationary blades through which a process gas stream is passed at high velocity. Unlike fluidized beds, the process gas mass flow can be set to suit the process, i. e. a smaller gas mass flow can be used at a higher velocity at exit from the blades to keep the bed in proper motion. Advantages are: (1) smaller reactor size with rapid start-up and program change, (2) faster and more precise processing of particles, resulting in a consistent product or process, (3) low process stream pressure losses which facilitate process gas recirculation, (4) ability to process widely graded and irregularly shaped feed stocks, and (5) simplicity of operation through real time control. The 'expanded' version of the TORBED reactor also permits fuel injection to generate process gas temperatures in excess of 1600 degrees C, and allows high gas flow rates with low pressure drop. When used to reprocess asphalt paving waste, the coal tar, used in some 25 per cent of existing roads in the Netherlands, can be easily removed and destroyed and the cleaned stone and the energy generated form the destruction of the coal tar, can be reused in creating new bitumen- containing asphalt paving. Excellent results are reported to have been obtained in pilot studies. Pilot trial also have been conducted on the combustion of wood waste for power generation, with encouraging results. Other pilot projects addressed alternative cementitious materials. 5 refs.

  8. Fly-ash-amended sand as filter media in bioretention cells to improve phosphorus removal. (United States)

    Zhang, Wei; Brown, Glenn O; Storm, Daniel E; Zhang, Hailin


    This study identified material with high phosphorus sorption suitable for bioretention filter media. Materials examined were fly ash, two expanded shales, peat moss, limestone, and two common Oklahoma soils--Teller loam and Dougherty sand. The peat moss was a phosphorus source, while the two soils, limestone, and one expanded shale had only modest sorption capacity. One expanded shale and the fly ash had significant phosphorus sorption. Fly ash is unsuitable for use in a pure form, as a result of its low permeability, but phosphorus sorption on the sand was increased significantly with the incorporation of small amounts of fly ash. Column leaching experiments found that the sand with 2.5 and 5% fly ash and the better expanded shale had linear, non-equilibrium transport retardation factors of 272, 1618, and 185, with first-order rate coefficients of 0.153, 0.0752, and 0.113 hour(-1), respectively. Desorption experiments showed that the phosphorus sorption on the sand/fly ash mixture is largely nonreversible. Transport simulation assuming a 1-m-deep sand/fly ash treatment layer, with 5% of the watershed area, showed that the sand/fly ash filter media could effectively treat 1 mg/L influent for 12 years in a paved watershed and 34 years in a grassed watershed before exceeding Oklahoma's scenic rivers' phosphorus criterion of 0.037 mg/L. Significant phosphorus removal would continue for over 100 years.

  9. 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)


    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.

  10. The humoral immune response of mice exposed to simulated road paving-like asphalt fumes. (United States)

    Anderson, Stacey E; Munson, Albert E; Tomblyn, Seth; Meade, B Jean; Diotte, Nicole M


    Asphalt is a complex mixture of organic molecules, including polycyclic aromatic hydrocarbons (PAH), which have been reported to cause serious adverse health effects in humans. Workers in manufacturing and construction trades exposed to asphalt are potentially at risk for being exposed to asphalt fumes and PAHs. Epidemiological investigations have collected mounting evidence that chemicals found in asphalt fumes present carcinogenic and possibly immunotoxic hazards. Studies evaluating the immunotoxic effects of asphalt fume are limited due to the large number of variables associated with asphalt fume exposures. This work investigates the immuno-toxic effects of road paving-like asphalt fume by analyzing the in vivo IgM response to a T-dependent antigen after exposure to whole, vapor, and particulate phase road paving-like asphalt fumes and asphalt fume condensate. Systemic exposures via intraperitoneal injection of asphalt fume condensate (at 0.625 mg/kg) and the particulate phase (at 5 mg/kg) resulted in significant reductions in the specific spleen IgM response to SRBC. Pharyngeal aspiration of the asphalt fume condensate (at 5 mg/kg) also resulted in significant suppression of the IgM response to SRBC. A significant reduction in the specific spleen IgM activity was observed after inhalation exposure to whole asphalt fumes (35 mg/m(3)) and the vapor components (11 mg/m(3)). Dermal exposures to the asphalt fume condensate resulted in significant reductions in the total (at 50 mg/kg) and specific (at 250 mg/kg) spleen IgM response to SRBC. These results demonstrate that exposure to road paving-like asphalt fumes is immunosuppressive through systemic, respiratory, and dermal routes of exposure in a murine model and raise concerns regarding the potential for adverse immunological effects.

  11. Tomographic and pathological findings of crazy-paving pattern

    Energy Technology Data Exchange (ETDEWEB)

    Vabo, Karen Amaral do; Damato, Simone Duarte [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil). Dept. of Radiology


    Objective: To describe high-resolution computed tomography findings in several diseases that run their course with the 'crazy-paving' pattern. Materials and Methods: The present study has evaluated seven patients with diagnoses of alveolar proteinosis, bronchioloalveolar carcinoma, lipoid pneumonia and pneumocystosis, correlating tomographic and pathological findings. Results: In the cases of pneumocystosis, the alveolar spaces were filled with foamy material where parasitic organisms intermingled with surfactants, fibrin and cell debris were observed. In the cases of bronchioloalveolar carcinoma, the septa were thickened by associated fibrosis or lymphangitis, with the alveolar walls internally lined with tumor cells, and production of mucus. In the patient with alveolar proteinosis, the septa were thickened by edema, with alveolar filling determined by lipoprotein. In the patient with mineral oil aspiration, the histopathological findings included alveolar septa thickening caused by cell proliferation, with presence of fat vacuoles in alveolar septa. Conclusion: The crazy-paving pattern offers a wide range of differential diagnoses and must be evaluated in conjunction with clinical findings. (author)

  12. Fusion characterization of biomass ash

    DEFF Research Database (Denmark)

    Ma, Teng; Fan, Chuigang; Hao, Lifang;


    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....

  13. 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


    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.

  14. Ash Properties of Alternative Biomass

    DEFF Research Database (Denmark)

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


    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....


    Energy Technology Data Exchange (ETDEWEB)



    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

  16. MAT 126 ASH Course Tutorial / Tutorialoutlet




    For more course tutorials visit   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...

  17. Ash3d: A finite-volume, conservative numerical model for ash transport and tephra deposition (United States)

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


    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.

  18. Production of pyroxene ceramics from the fine fraction of incinerator bottom ash. (United States)

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


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

  19. MGT 330 ASH Course Tutorial / Tutorialoutlet




    For more course tutorials visit   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...

  20. Gas/aerosol-ash interaction in volcanic plumes: New insights from surface analyses of fine ash particles (United States)

    Delmelle, Pierre; Lambert, Mathieu; Dufrêne, Yves; Gerin, Patrick; Óskarsson, Niels


    The reactions occurring between gases/aerosols and silicate ash particles in volcanic eruption plumes remain poorly understood, despite the fact that they are at the origin of a range of volcanic, environmental, atmospheric and health effects. In this study, we apply X-ray photoelectron spectroscopy (XPS), a surface-sensitive technique, to determine the chemical composition of the near-surface region (2-10 nm) of nine ash samples collected from eight volcanoes. In addition, atomic force microscopy (AFM) is used to image the nanometer-scale surface structure of individual ash particles isolated from three samples. We demonstrate that rapid acid dissolution of ash occurs within eruption plumes. This process is favoured by the presence of fluoride and is believed to supply the cations involved in the deposition of sulphate and halide salts onto ash. AFM imaging also has permitted the detection of extremely thin (< 10 nm) coatings on the surface of ash. This material is probably composed of soluble sulphate and halide salts mixed with sparingly soluble fluoride compounds. The surface approach developed here offers promising aspects for better appraising the role of gas/aerosol-ash interaction in dictating the ability of ash to act as sinks for various volcanic and atmospheric chemical species as well as sources for others.

  1. Physical and chemical characterization of asphalt (bitumen) paving exposures. (United States)

    Herrick, Robert F; McClean, Michael D; Meeker, John D; Zwack, Leonard; Hanley, Kevin


    The purpose of this research was to characterize the physical and chemical properties of asphalt (bitumen) fume and vapor in hot mix asphalt roadway paving operations. Area and personal air samples were taken using real-time equipment and extractive sampling and analytical methods to determine worker asphalt exposure, as well as to characterize the properties of the particulate and vapor phase components. Analysis of personal inhalation and dermal samples by gas chromatography/mass spectroscopy showed that the polycyclic aromatic hydrocarbon profile is dominated by compounds with molecular weights below 228, and that substituted and heterocyclic polycyclic aromatic hydrocarbons comprised approximately 71% of the detectable mass concentration (vapor and particulate combined). Principal components analysis shows that the polycyclic aromatic hydrocarbons with molecular weights greater than 190 are the driving force behind the polycyclic aromatic compound exposures measured for the dermal and particulate phases; there was no clear trend for the vapor phase Most of the aerosol particles are fine (mass median aerodynamic diameter 1.02 microm; count median diameter 0.24 microm).

  2. The demonstration of an advanced cyclone coal combustor, with internal sulfur, nitrogen, and ash control for the conversion of a 23 MMBTU/hour oil fired boiler to pulverized coal

    Energy Technology Data Exchange (ETDEWEB)

    Zauderer, B.; Fleming, E.S.


    This work contains to the final report of the demonstration of an advanced cyclone coal combustor. Titles include: Chronological Description of the Clean Coal Project Tests,'' Statistical Analysis of Operating Data for the Coal Tech Combustor,'' Photographic History of the Project,'' Results of Slag Analysis by PA DER Module 1 Procedure,'' Properties of the Coals Limestone Used in the Test Effort,'' Results of the Solid Waste Sampling Performed on the Coal Tech Combustor by an Independent Contractor During the February 1990 Tests.'' (VC)

  3. Volcanic ash as fertiliser for the surface ocean

    Directory of Open Access Journals (Sweden)

    B. Langmann


    Full Text Available Iron is a key limiting micro-nutrient for marine primary productivity. It can be supplied to the ocean by atmospheric dust deposition. Volcanic ash deposition into the ocean represents another external and so far largely neglected source of iron. This study demonstrates strong evidence for natural fertilisation in the iron-limited oceanic area of the NE Pacific, induced by volcanic ash from the eruption of Kasatochi volcano in August 2008. Atmospheric and oceanic conditions were favourable to generate a massive phytoplankton bloom in the NE Pacific Ocean which for the first time strongly suggests a connection between oceanic iron-fertilisation and volcanic ash supply.

  4. Volcanic ash as fertiliser for the surface ocean

    Directory of Open Access Journals (Sweden)

    B. Langmann


    Full Text Available Iron is a key limiting micro-nutrient for marine primary productivity. It can be supplied to the ocean by atmospheric dust deposition. Volcanic ash deposition into the ocean represents another external and so far largely neglected source of iron. This study demonstrates strong evidence for natural fertilisation in the iron-limited oceanic area of the NE Pacific, induced by volcanic ash from the eruption of Kasatochi volcano in August 2008. Atmospheric and oceanic conditions were favourable to generate a massive phytoplankton bloom in the NE Pacific Ocean which for the first time establishes a causal connection between oceanic iron-fertilisation and volcanic ash supply.

  5. Volcanic ash melting under conditions relevant to ash turbine interactions. (United States)

    Song, Wenjia; Lavallée, Yan; Hess, Kai-Uwe; Kueppers, Ulrich; Cimarelli, Corrado; Dingwell, Donald B


    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.

  6. Ash Management Review—Applications of Biomass Bottom Ash

    Directory of Open Access Journals (Sweden)

    Harpuneet S. Ghuman


    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.

  7. Utilization of coal ash from fluidized-bed combustion boilers as road base material; Sekitandaki ryudoso boiler kara no sekitanbai no robanzai to shite no riyo

    Energy Technology Data Exchange (ETDEWEB)

    Shibata, Y. [Kawasaki Heavy Industries, Ltd., Kobe (Japan); Kozasa, K. [Center for Coal Utilization, Japan, Tokyo (Japan); Tsuzura, K. [Naruto Salt Mfg. Co. Ltd., Tokushima (Japan); Izumi, H. [Nippon Hodo Co. Ltd., Tokyo (Japan)


    Coal ash from the fluidized bed boiler is evaluated for its properties as is, as solidified or granulated, and as the roadbed material. The coal ash tested in the experiment is a mixture of ash from the fluidized bed boiler bottom, ash from the cyclone separator, and ash from the bag filter. In the manufacture of solid or granulated bodies, coal ashes are kneaded in water whose amount puts the mixture near the plasticization limit, are pressed in a low-pressure press and made into solid bodies by a 15-hour curing in 60degC saturated steam, and the solid bodies are crushed into solid granules. A content release test is conducted about the release of dangerous substances, and road paving experiments are conducted to learn the workability and serviceability of the granulated material as a road paving material. A study of the experimental results discloses what is mentioned below. Coal ash containing 10-20vol% of CaO and 15vol% or less of unburnt carbon turns into a high-strength solid after curing in saturated steam whose temperature is not higher than 60degC. The granulated solid satisfies the standards that an upper subbase material is expected to satisfy. It also meets the environmental standards in a release content test for soil set forth by Environment Agency notification No.46. 8 refs., 8 figs., 4 tabs.

  8. MGT 401 ASH Course Tutorial / Tutorialoutlet




    For more course tutorials visit   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) ...

  9. Melting Behavior of Volcanic Ash relevant to Aviation Ash Hazard (United States)

    Song, W.; Hess, K.; Lavallee, Y.; Cimarelli, C.; Dingwell, D. B.


    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

  10. The relation between pre-eruptive bubble size distribution, ash particle morphology, and their internal density: Implications to volcanic ash transport and dispersion models (United States)

    Proussevitch, Alexander


    Parameterization of volcanic ash transport and dispersion (VATD) models strongly depends on particle morphology and their internal properties. Shape of ash particles affects terminal fall velocities (TFV) and, mostly, dispersion. Internal density combined with particle size has a very strong impact on TFV and ultimately on the rate of ash cloud thinning and particle sedimentation on the ground. Unlike other parameters, internal particle density cannot be measured directly because of the micron scale sizes of fine ash particles, but we demonstrate that it varies greatly depending on the particle size. Small simple type ash particles (fragments of bubble walls, 5-20 micron size) do not contain whole large magmatic bubbles inside and their internal density is almost the same as that of volcanic glass matrix. On the other side, the larger compound type ash particles (>40 microns for silicic fine ashes) always contain some bubbles or the whole spectra of bubble size distribution (BSD), i.e. bubbles of all sizes, bringing their internal density down as compared to simple ash. So, density of the larger ash particles is a function of the void fraction inside them (magmatic bubbles) which, in turn, is controlled by BSD. Volcanic ash is a product of the fragmentation of magmatic foam formed by pre-eruptive bubble population and characterized by BSD. The latter can now be measured from bubble imprints on ash particle surfaces using stereo-scanning electron microscopy (SSEM) and BubbleMaker software developed at UNH, or using traditional high-resolution X-Ray tomography. In this work we present the mathematical and statistical formulation for this problem connecting internal ash density with particle size and BSD, and demonstrate how the TFV of the ash population is affected by variation of particle density.

  11. Market assessment of PFBC ash use

    Energy Technology Data Exchange (ETDEWEB)

    Bland, A. E.; Brown, T. H., Western Research Institute


    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).

  12. Ash in the Soil System (United States)

    Pereira, P.


    Ash is the organic and inorganic residue produced by combustion, under laboratory and field conditions. This definition is far away to be accepted. Some researchers consider ash only as the inorganic part, others include also the material not completely combusted as charcoal or biochar. There is a need to have a convergence about this question and define clear "what means ash". After the fire and after spread ash onto soil surface, soil properties can be substantially changed depending on ash properties, that can be different according to the burned residue (e.g wood, coal, solid waste, peppermill, animal residues), material treatment before burning, time of exposition and storage conditions. Ash produced in boilers is different from the produced in fires because of the material diferent propertie and burning conditions. In addition, the ash produced in boilers is frequently treated (e.g pelletization, granulation, self curing) previously to application, to reduce the negative effects on soil (e.g rapid increase of pH, mycorrhiza, fine roots of trees and microfauna). These treatments normally reduce the rate of nutrients dissolution. In fires this does not happen. Thus the implications on soil properties are logically different. Depending on the combustion temperature and/or severity, ash could have different physical (e.g texture, wettability) and chemical properties (e.g amount and type of total and leached nutrients) and this will have implications on soil. Ash can increase and decrease soil aggregation, wettablity and water retention, bulk density, runoff and water infiltration. Normally, ash increases soil pH, Electrical Conductivity, and the amount of some basic nutrients as calcium, magnesium, sodium and potassium. However it is also a potential source of heavy metals, especially if ash pH is low. However the effect of ash on soil in space and time depends especially of the ash amount and characteristics, fire temperature, severity, topography, aspect

  13. Ashes 2013 - A network theory analysis of Cricket strategies


    Mukherjee, Satyam


    We demonstrate in this paper the use of tools of complex network theory to describe the strategy of Australia and England in the recently concluded Ashes 2013 Test series. Using partnership data made available by cricinfo during the Ashes 2013 Test series, we generate batting partnership network (BPN) for each team, in which nodes correspond to batsmen and links represent runs scored in partnerships between batsmen. The resulting network display a visual summary of the pattern of run-scoring ...

  14. 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...... of the treated products for reuse in construction or farming sectors should be explored further, as should the possibility of recycling of valuable, extracted elements in the metallurgical industry....

  15. Size distribution of rare earth elements in coal ash (United States)

    Scott, Clinton T.; Deonarine, Amrika; Kolker, Allan; Adams, Monique; Holland, James F.


    Rare earth elements (REEs) are utilized in various applications that are vital to the automotive, petrochemical, medical, and information technology industries. As world demand for REEs increases, critical shortages are expected. Due to the retention of REEs during coal combustion, coal fly ash is increasingly considered a potential resource. Previous studies have demonstrated that coal fly ash is variably enriched in REEs relative to feed coal (e.g, Seredin and Dai, 2012) and that enrichment increases with decreasing size fractions (Blissett et al., 2014). In order to further explore the REE resource potential of coal ash, and determine the partitioning behavior of REE as a function of grain size, we studied whole coal and fly ash size-fractions collected from three U.S commercial-scale coal-fired generating stations burning Appalachian or Powder River Basin coal. Whole fly ash was separated into , 5 um, to 5 to 10 um and 10 to 100 um particle size fractions by mechanical shaking using trace-metal clean procedures. In these samples REE enrichments in whole fly ash ranges 5.6 to 18.5 times that of feedcoals. Partitioning results for size separates relative to whole coal and whole fly ash will also be reported. 

  16. Dielectric properties of fly ash

    Indian Academy of Sciences (India)

    S C Raghavendra; R L Raibagkar; A B Kulkarni


    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).

  17. Ash Aggregates in Proximal Settings (United States)

    Porritt, L. A.; Russell, K.


    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

  18. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles

    Directory of Open Access Journals (Sweden)

    A. Kylling


    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.

  19. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles (United States)

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


    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.

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

    Directory of Open Access Journals (Sweden)

    S. L. Summoogum-Utchanah


    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.

  1. Ash dispersal dynamics: state of the art and perspectives (United States)

    Sulpizio, R.


    Volcanic ash, during dispersal and deposition, is among the major hazards from explosive eruptions. Volcanic ash fallout can disrupt communities downwind, interrupt surface transportation networks and lead to closure of airports. Airborne ash seriously threatens modern jet aircraft in flight. In several documented cases, encounters between aircraft and volcanic clouds have resulted in engine flameout and near crashes, so there is a need to accurately predict the trajectory of volcanic ash clouds in order to improve aviation safety and reduce economic losses. The ash clouds affect aviation even in distal regions, as demonstrated by several eruptions with far-range dispersal. Recent examples include Crater Peak 1992, Tungurahua 1999-2001, Mount Cleveland 2001, Chaitén 2008, Eyjafjallajökull 2010, Grimsvötn 2011, and Cordón-Caulle 2011. Amongst these, the April-May 2010 eruption of Eyjafjallajökull in Iceland provoked the largest civil aviation breakdown. Accumulation of tephra can produce roof collapse, interruption of lifelines (roads, railways, etc.), disruption to airport operations, and damage to communications and electrical power lines. Deposition of ash decreases soil permeability, increases surface runoff, and promotes floods. Ash leaching can result in the pollution of water resources, damage to agriculture, pastures, and livestock, impinge on aquatic ecosystems, and alteration of the geochemical environment on the seafloor. Despite the potential big impact, the dispersal dynamics of volcanic ash is still an unsolved problem for volcanologists, which claims for fiture high level research. Here, a critical overview about models (field, experimental and numerical) for inversion of field data to gain insights on physics of dispersal of volcanic ash is proposed. A special focus is devoted to some physical parameters that are far from a satisfactory inversion (e.g. reconstruction of total grain size distribution), and clues for future research are suggested.

  2. 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)


    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.

  3. Scale-Up and Demonstration of Dly Ash Ozonation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Larry LaBuz; Rui Afonso


    This is the first Quarterly report under DOE Cooperative Agreement No.: DE-FC26-03NT41730. Due a number of circumstances, mostly associated with subcontractor agreements, the actual beginning of the project has been delayed from its original award date of March 5, 2003. DOE's Project Manager has been kept informed (verbally) by PPL's Project Manager throughout this period. Because of this delay, this is the first quarterly report and it refers to the time period from the official project authorization date to June 2004. In addition, this report is essentially a review of the project objectives and approach, with a brief update on the recent ''kick-off'' and site visit activities in the Results and Discussion section.

  4. Scale-Up and Demonstration of Fly Ash Ozonation Tech

    Energy Technology Data Exchange (ETDEWEB)

    Larry La Buz; Rui Afonso


    This is the third quarterly report under DOE Cooperative Agreement No.: DE-FC26-03NT41730. Due a number of circumstances, mostly associated with subcontractor agreements, the actual beginning of the project was delayed from its original award date of March 5, 2003. DOE's Project Manager was kept informed (verbally) by PPL's Project Manager throughout this period. Because of this delay, this is the third quarterly report and it refers to the time period from October to December 2004. As the project is in its ''pre-deployment'' stage, no results are available. This report summarizes the ongoing activities and provides an updated schedule. No significant issues or concerns are identified.

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

    Energy Technology Data Exchange (ETDEWEB)

    Larry LaBuz; Rui Afonso


    This is the fourth quarterly report under DOE Cooperative Agreement No.: DE-FC26-03NT41730. Due a number of circumstances, mostly associated with subcontractor agreements, the actual beginning of the project was delayed from its original award date of March 5, 2003. DOE's Project Manager was kept informed (verbally) by PPL's Project Manager throughout this period. Because of this delay, this is the fourth quarterly report and it refers to the time period from January to March 2004. The on-site deployment and testing of the ozonation system took place during this period. This report summarizes these activities including some preliminary results. No significant issues or concerns are identified.

  6. HIS 103 ASH course tutorial/tutorialoutlet


    NARESH 1


    For more course tutorials visit   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...

  7. Epoxy asphalt concrete paving on the deck of long-span steel bridges

    Institute of Scientific and Technical Information of China (English)

    HUANG Wei; QIAN Zhendong; CHEN Gang; YANG Jun


    It is the first systematic research in the world on the composition design of epoxy asphalt concrete as pav- ing material. Material characteristics and service perform- ance of mixture, fatigue resistance characteristics of epoxy asphalt concrete by the fatigue test of complex beam have also been described. This research indicates that epoxy asphalt concrete is a good type of paving material. Research results have been applied successfully in the paving of steel deck of the Second Nanjing Yangtze River Bridge (SNYRB). It provides a new paving type for long-span steel bridges of China and has a bright application prospect.

  8. PAVE LOW III: interior lighting reconfiguration for night lighting and night vision goggle compatibility. (United States)

    Task, H L; Griffin, L L


    The PAVE LOW III aircraft is a modified HH-53H helicopter that has a low altitude--below 30.48 m (100 ft)--night/day rescue mission. The desired night flying configuration is for the pilot to wear night vision goggles (NVGs) to fly the aircraft while the copilot, without NVGs, observes the video display and monitors the aircraft instruments. The problems of NVG incompatibility in the cockpit were successfully countered using several light control techniques. The light control modifications were evaluated on the ground in the PAVE LOW III helicopter at Kirtland AFB in April, 1980, by PAVE LOW instructor pilots. The evaluation results were extremely positive.

  9. Leaching from biomass combustion ash

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard


    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...

  10. Emerald Ash Borer (Coleoptera: Buprestidae) (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. Multiphase flow modelling of volcanic ash particle settling in water using adaptive unstructured meshes


    Jacobs, C.T.; Collins, G S; M. D. Piggott; S. C. Kramer; Wilson, C.R.G.


    Small-scale experiments of volcanic ash particle settling in water have demonstrated that ash particles can either settle slowly and individually, or rapidly and collectively as a gravitationally unstable ash-laden plume. This has important implications for the emplacement of tephra deposits on the seabed. Numerical modelling has the potential to extend the results of laboratory experiments to larger scales and explore the conditions under which plumes may form and persist, but many existing ...

  12. Characterizing worker exposure to bitumen during hot mix paving and asphalt mixing operations. (United States)

    Burstyn, Igor; Ferrari, Pietro; Wegh, Hillion; Heederik, Dick; Kromhout, Hans


    A survey of bitumen exposure was carried out during hot mix paving and asphalt mixing. Four methods of characterizing and quantifying bitumen fume in inhalable particles were used: gravimetric, infrared spectroscopy, gas chromatography, and total absorbance (of the particle filter surface). Dermal deposition of bitumen was assessed by determination of cyclohexanesoluble matter in the material collected by paper or cotton pads worn on the inside of a person's wrists. The researchers studied the correlation patterns between results of these methods using pairwise correlation coefficients and principal component analysis (for air concentrations only). For hot mix paving, within- and between-worker variance components were evaluated, adjusting for area paved. Collected fume was dark in color and mainly consisted of aliphatic hydrocarbons of less than 20 carbon atoms. Inconsistent correlation patterns between dermal deposition and air levels were observed. Quantification of organic matter using either infrared spectroscopy or gas chromatography appeared to be good methods for monitoring inhalable bitumen fume. Cotton pads seem to be more promising than paper pads for measuring dermal exposure during paving. Paving workers were uniformly exposed to bitumen fume. Assessment of the uniformity of dermal exposure depended on the type of pad used. Day-to-day variability and intensity of inhalable and dermal bitumen exposures depended on area paved. The small size of the study limits the potential application of the results to the asphalt industry in general. More research is needed to develop a valid and inexpensive method of assessing total bitumen exposure.

  13. 49 CFR 230.69 - Ash pans. (United States)


    ... 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...

  14. 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.


    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.

  15. Applications of fly ash in synthesizing low-cost MMCs for automotive and other applications (United States)

    Rohatgi, P. K.; Weiss, D.; Gupta, Nikhil


    This paper summarizes attempts to incorporate fly ash into aluminum castings to decrease the energy content, material content, cost, and weight of selected industrial components, while also improving selected properties. It is shown that fly ash can be incorporated into an aluminum-alloy matrixusing stir casting and pressure infiltration techniques. The sand and permanent mold castings, which included differential vovers, intake manifolds brake drums, and outdoor equipment castings including post caps, demonstrate adequate castability of aluminum melts containing up to 10 vol.% fly-ash particles. The potential cost, energy, and pollution savings as a result of incorporation of fly ash in aluminum are discussed in the paper.

  16. Ash pollen allergy: reliable detection of sensitization on the basis of IgE to Ole e 1. (United States)

    Imhof, Konrad; Probst, Elisabeth; Seifert, Burkhardt; Regenass, Stephan; Schmid-Grendelmeier, Peter

    Background: Alongside hazel, alder and birch pollen allergies, ash pollen allergy is a relevant cause of hay fever during spring in the European region. For some considerable time, ash pollen allergy was not routinely investigated and its clinical relevance may well have been underestimated, particularly since ash and birch tree pollination times are largely the same. Ash pollen extracts are not yet well standardized and diagnosis is therefore sometimes unreliable. Olive pollen, on the other hand, is strongly cross-reactive with ash pollen and is apparently better standardized. Therefore, the main allergen of olive pollen, Ole e 1, has been postulated as a reliable alternative for the detection of ash pollen sensitization. Methods: To determine to what extent specific IgE against Ole e 1 in patients with ash pollen allergy is relevant, we included 183 subjects with ash pollen allergy displaying typical symptoms in March/April and positive skin prick test specific IgE against Ole e 1 (t224) and ash pollen (t25) and various birch allergens (Bet v 1, Bet v 2/v 4) in a retrospective study. Results: A significant correlation was seen between specific IgE against Ole e 1 and ash pollen, but also to a slightly lesser extent between IgE against Ole e 1 and skin prick test with ash pollen, the latter being even higher than IgE and skin prick test both with ash pollen. No relevant correlation was found with birch pollen allergens, demonstrating the very limited cross-reactivity between ash and birch pollen. Conclusion: It appears appropriate to determine specific IgE against Ole e 1 instead of IgE against ash pollen to detect persons with ash pollen allergy. Our findings may also support the idea of using possibly better standardized or more widely available olive pollen extracts instead of ash pollen extract for allergen-specific immunotherapy.

  17. Assessing the effects of FBC ash treatments of metal-contaminated soils using life history traits and metal bioaccumulation analysis of the earthworm Eisenia andrei

    Energy Technology Data Exchange (ETDEWEB)

    Grumiaux, F.; Demuynck, S.; Schikorski, D.; Lemiere, S.; Lepretre, A. [Universite Lille Nord de France, Villeneuve Dascq (France)


    Earthworms (Eisenia andrei) were exposed, in controlled conditions, to metal-contaminated soils previously treated in situ with two types of fluidized bed combustion ashes. Effects on this species were determined by life history traits analysis. Metal immobilizing efficiency of ashes was indicated by metal bioaccumulation. Ashes-treated soils reduced worm mortality compared to the untreated soil. However, these ashes reduced both cocoon hatching success and hatchlings numbers compared to the untreated soil. In addition, sulfo-calcical ashes reduced or delayed worm maturity and lowered cocoon production compared to silico-alumineous ones. Metal immobilizing efficiency of ashes was demonstrated for Zn, Cu and to a lesser extent Pb. Only silico-alumineous ashes reduced Cd bioaccumulation, although Cd was still bioconcentrated. Thus, although ash additions to metal-contaminated soils may help in immobilizing metals, their use might result, depending on the chemical nature of ashes, to severe detrimental effects on earthworm reproduction with possible long term consequences to populations.

  18. AshMeadowsNaucorid_CH (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...

  19. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.


    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.)

  20. Characterization of Coal Tar Pitch and Paving Pitch by UV, EA and NMR%Characterization of Coal Tar Pitch and Paving Pitch by UV,EA and NMR

    Institute of Scientific and Technical Information of China (English)

    XIAO Yan-hua; FENG Rui-jie; CAO Su-mei; LIU Xiang-yong; GAO Ting; PAN Zhi-quan


    In order to enlarge the use of coal tar pitch(CTP) in paving road, CTP and 60th paving pitch (PP) were extracted by n-heptane, toluene and ethanol step by step in a Soxhlet apparatus. The three fractions of CTP and PP were detected using UV-absorption(UV-A) ,elemental analyses(EA) and nuclear magnetic resonance (NMR) firstly as a whole unit after quality characterization of physical nature of CTP and PP were finished. The CTP had more saturate aliphatie and residue compounds dissolved in ethanol. On the other hand there were more continental type structures of aromatic ring than that of PP. There was almost no residue in PP after extracted by ethanol. The results explained why CTP was crisp in cold winter and was soften in summer. The following research will focus on how to change the chemical construction of CTP into the relative similar structures with those of PP through adding polymer.


    Energy Technology Data Exchange (ETDEWEB)

    David J. Hassett; Loreal V. Heebink


    The Minnesota Pollution Control Agency (MPCA) approved the use of coal ash in soil stabilization, indicating that environmental data needed to be generated. The overall project goal is to evaluate the potential for release of constituents into the environment from ash used in soil stabilization projects. Supporting objectives are: (1) To ensure sample integrity through implementation of a sample collection, preservation, and storage protocol to avoid analyte concentration or loss. (2) To evaluate the potential of each component (ash, soil, water) of the stabilized soil to contribute to environmental release of analytes of interest. (3) To use laboratory leaching methods to evaluate the potential for release of constituents to the environment. (4) To facilitate collection of and to evaluate samples from a field runoff demonstration effort. The results of this study indicated limited mobility of the coal combustion fly ash constituents in laboratory tests and the field runoff samples. The results presented support previous work showing little to negligible impact on water quality. This and past work indicates that soil stabilization is an environmentally beneficial CCB utilization application as encouraged by the U.S. Environmental Protection Agency. This project addressed the regulatory-driven environmental aspect of fly ash use for soil stabilization, but the demonstrated engineering performance and economic advantages also indicate that the use of CCBs in soil stabilization can and should become an accepted engineering option.

  2. 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.)


    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.

  3. Tested Demonstrations. (United States)

    Sands, Robert; And Others


    Procedures for two demonstrations are provided. The solubility of ammonia gas in water is demonstrated by introducing water into a closed can filled with the gas, collapsing the can. The second demonstration relates scale of standard reduction potentials to observed behavior of metals in reactions with hydrogen to produce hydrogen gas. (Author/JN)

  4. Volcanic ash infrared signature: realistic ash particle shapes compared to spherical ash particles


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


    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...

  5. Spreading dynamic of viscous volcanic ash in stimulated jet engine conditions (United States)

    song, wenjia; Lavallée, Yan; Hess, Kai-Uwe; Kueppers, Ulrich; Cimarelli, Corrado


    The ingestion of volcanic ash is widely recognised as a potentially fatal hazard for aircraft operation. The volcanic ash deposition process in a jet turbine is potentially complex. Volcanic ash in the air stream enters the inner liners of the combustors and partially or completely melts under the flames up to 2000 °C, at which point part of the ash deposits in the combustor fuel nozzle. Molten volcanic particles within high energy airflow escape the combustor to enter the turbine and impact the stationary (e.g., inlet nozzle guide vanes) and rotating airfoils (e.g., first stage high-pressure turbine blades) at high speed (up to Mach 1.25) in different directions, with the result that ash may stick, flow and remain liquid or solidify. Thus, the wetting behaviour of molten volcanic ash particle is fundamental to investigate impingement phenomena of ash droplet on the surface of real jet engine operation. The topic of wetting has received tremendous interest from both fundamental and applied points of view. However, due to the interdisciplinary gap between jet engine engineering and geology science, explicit investigation of wetting behaviour of volcanic ash at high temperature is in its infancy. We have taken a big step towards meeting this challenge. Here, we experimentally and theoretically investigate the wetting behaviour of viscous volcanic ash over a wide temperature range from 1100 to 1550 °C using an improved sessile-drop method. The results of our experiment demonstrate that temperature and viscosity play a critical role in determining the wetting possibility and governing the spreading kinetics of volcanic ash at high temperatures. Our systemic analysis of spreading of molten volcanic ash systems allows us to report on the fundamental differences between the mechanisms controlling spreading of organic liquids at room temperature and molten volcanic ash droplets.

  6. Characterization of ashes from biofuels

    Energy Technology Data Exchange (ETDEWEB)

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


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

  7. Controlling formaldehyde emissions with boiler ash. (United States)

    Cowan, Jennifer; Abu-Daabes, Malyuba; Banerjee, Sujit


    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 (United States)

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


    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. Tested Demonstrations. (United States)

    Gilbert, George L., Ed.


    Describes two laboratory demonstrations in chemistry. One uses dry ice, freon, and freezer bags to demonstrate volume changes, vapor-liquid equilibrium, a simulation of a rain forest, and vaporization. The other uses the clock reaction technique to illustrate fast reactions and kinetic problems in releasing carbon dioxide during respiration. (TW)

  10. Complete Demonstration. (United States)

    Yelon, Stephen; Maddocks, Peg


    Describes four-step approach to educational demonstration: tell learners they will have to perform; what they should notice; describe each step before doing it; and require memorization of steps. Examples illustrate use of this process to demonstrate a general mental strategy, and industrial design, supervisory, fine motor, and specific…

  11. Tested Demonstrations. (United States)

    Gilbert, George L., Ed.


    Outlines a simple, inexpensive way of demonstrating electroplating using the reaction between nickel ions and copper metal. Explains how to conduct a demonstration of the electrolysis of water by using a colored Na2SO4 solution as the electrolyte so that students can observe the pH changes. (TW)

  12. Tested Demonstrations. (United States)

    Gilbert, George L., Ed.


    Discusses a supplement to the "water to rose" demonstration in which a pink color is produced. Also discusses blood buffer demonstrations, including hydrolysis of sodium bicarbonate, simulated blood buffer, metabolic acidosis, natural compensation of metabolic acidosis, metabolic alkalosis, acidosis treatment, and alkalosis treatment. Procedures…

  13. Tested Demonstrations. (United States)

    Gilbert, George L., Ed.


    Free radical chlorination of methane is used in organic chemistry to introduce free radical/chain reactions. In spite of its common occurrence, demonstrations of the reaction are uncommon. Therefore, such a demonstration is provided, including background information, preparation of reactants/reaction vessel, introduction of reactants, irradiation,…

  14. Mercury capture by selected Bulgarian fly ashes: Influence of coal rank and fly ash carbon pore structure on capture efficiency (United States)

    Kostova, I.J.; Hower, J.C.; Mastalerz, Maria; Vassilev, S.V.


    Mercury capture by fly ash C was investigated at five lignite- and subbituminous-coal-burning Bulgarian power plants (Republika, Bobov Dol, Maritza East 2, Maritza East 3, and Sliven). Although the C content of the ashes is low, never exceeding 1.6%, the Hg capture on a unit C basis demonstrates that the low-rank-coal-derived fly ash carbons are more efficient in capturing Hg than fly ash carbons from bituminous-fired power plants. While some low-C and low-Hg fly ashes do not reveal any trends of Hg versus C, the 2nd and, in particular, the 3rd electrostatic precipitator (ESP) rows at the Republika power plant do have sufficient fly ash C range and experience flue gas sufficiently cool to capture measurable amounts of Hg. The Republika 3rd ESP row exhibits an increase in Hg with increasing C, as observed in other power plants, for example, in Kentucky power plants burning Appalachian-sourced bituminous coals. Mercury/C decreases with an increase in fly ash C, suggesting that some of the C is isolated from the flue gas stream and does not contribute to Hg capture. Mercury capture increases with an increase in Brunauer-Emmett-Teller (BET) surface area and micropore surface area. The differences in Hg capture between the Bulgarian plants burning low-rank coal and high volatile bituminous-fed Kentucky power plants suggests that the variations in C forms resulting from the combustion of the different ranks also influence the efficiency of Hg capture. ?? 2010 Elsevier Ltd.

  15. Hail formation triggers rapid ash aggregation in volcanic plumes. (United States)

    Van Eaton, Alexa R; Mastin, Larry G; Herzog, Michael; Schwaiger, Hans F; Schneider, David J; Wallace, Kristi L; Clarke, Amanda B


    During explosive eruptions, airborne particles collide and stick together, accelerating the fallout of volcanic ash and climate-forcing aerosols. This aggregation process remains a major source of uncertainty both in ash dispersal forecasting and interpretation of eruptions from the geological record. Here we illuminate the mechanisms and timescales of particle aggregation from a well-characterized 'wet' eruption. The 2009 eruption of Redoubt Volcano, Alaska, incorporated water from the surface (in this case, a glacier), which is a common occurrence during explosive volcanism worldwide. Observations from C-band weather radar, fall deposits and numerical modelling demonstrate that hail-forming processes in the eruption plume triggered aggregation of ∼95% of the fine ash and stripped much of the erupted mass out of the atmosphere within 30 min. Based on these findings, we propose a mechanism of hail-like ash aggregation that contributes to the anomalously rapid fallout of fine ash and occurrence of concentrically layered aggregates in volcanic deposits.

  16. Monitoring Volcanic Ash with MSG Seviri Image and RGB Application (United States)

    Erturk, Aydin Gurol; Kerkman, Jochen


    The eruption from the Eyjafjallajökull Volcano, Iceland recently became a high importance for the Meteorological Institutes, Aviation, Satellite Centers and other related institutions. Urgent forecasts were requested by the air control centers, aviation industry and even the passengers who stuck at the airports. It was announced that thousands of flights are canceled; hundreds of thousands of passengers affected and the airlines lost around 1.7 billion dollars in April-May 2010. This is the worst aviation crises. MSG (METEOSAT Second Generation) SEVIRI (Spinning Enhanced Visible and Infrared Imagery) with its 11 narrow and 1 broad band channels have been providing a worth of data sources for nowcasting and very short forecasting. SEVIRI images and RGB applications have been acted an important role to monitor Volcanic Ash during above aviation crises. SEVIRI has an infrared channel (centered @8.7 micron) which is sensitive sand, dust and ash in the atmosphere. In this study we present Ash RGB applications derived from SEVIRI data to monitor and track Ash clouds over Europe. Two main eruptions during 14-20 April and 7-17 May 2010 will be demonstrated. In addition to this, we will propose an Ash product algorithm and discuss its weakness and strength.

  17. Volcanic ash plume identification using polarization lidar: Augustine eruption, Alaska (United States)

    Sassen, Kenneth; Zhu, Jiang; Webley, Peter W.; Dean, K.; Cobb, Patrick


    During mid January to early February 2006, a series of explosive eruptions occurred at the Augustine volcanic island off the southern coast of Alaska. By early February a plume of volcanic ash was transported northward into the interior of Alaska. Satellite imagery and Puff volcanic ash transport model predictions confirm that the aerosol plume passed over a polarization lidar (0.694 mm wavelength) site at the Arctic Facility for Atmospheric Remote Sensing at the University of Alaska Fairbanks. For the first time, lidar linear depolarization ratios of 0.10 – 0.15 were measured in a fresh tropospheric volcanic plume, demonstrating that the nonspherical glass and mineral particles typical of volcanic eruptions generate strong laser depolarization. Thus, polarization lidars can identify the volcanic ash plumes that pose a threat to jet air traffic from the ground, aircraft, or potentially from Earth orbit.

  18. DMPD: Toll-like receptors: paving the path to T cell-driven autoimmunity? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17888644 Toll-like receptors: paving the path to T cell-driven autoimmunity? Marsla...nd BJ, Kopf M. Curr Opin Immunol. 2007 Dec;19(6):611-4. Epub 2007 Sep 21. (.png) (.svg) (.html) (.csml) Show receptors: paving the path to T cell-driven autoimmunity? PubmedID 17888644 Title Toll-like recep...tors: paving the path to T cell-driven autoimmunity? Authors Marsland BJ, Kopf M.

  19. The use of coal mining wastes for manufacturing paving materials; Los Esteriles del Carbon como Materia Prima para la Fabricacion de Materiales para Pavimentacion

    Energy Technology Data Exchange (ETDEWEB)



    This project was aimed at proving the technical feasibility of the use of coal mining wastes in the manufacturing of paving materials: floor-tiles, flags, paving-stones, grit stones, etc. The study proved that coal mining wastes in a mixture with other raw materials can be used in the manufacturing of paving materials: floor-tiles, paving-stones, grit stones.

  20. Tested Demonstrations. (United States)

    Gilbert, George L.


    Included are three demonstrations that include the phase change of ice when under pressure, viscoelasticity and colloid systems, and flame tests for metal ions. The materials, procedures, probable results, and applications to real life situations are included. (KR)

  1. Tested Demonstrations. (United States)

    Gilbert, George L., Ed.


    Presents three demonstrations suitable for undergraduate chemistry classes. Focuses on experiments with calcium carbide, the induction by iron of the oxidation of iodide by dichromate, and the classical iodine clock reaction. (ML)

  2. Behavior study of trace elements in pulverized lignite, bottom ash, and fly ash of Amyntaio power station, Greece. (United States)

    Megalovasilis, Pavlos; Papastergios, Georgios; Filippidis, Anestis


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

  3. Research on the Anticorrosion Coating Under the Paved Layer for Highway Steel Box Bridge Deck

    Institute of Scientific and Technical Information of China (English)

    SHEN Cheng-jin; MING Tu-zhang; HU Guang-wei; OU Xue-mei; GEN Ou


    The corrosion of the anticorrosion coating and the defects of the asphalt concrete paved layer have been investigated on long-span steel box bridge decks. The anticorrosion coating lies in the middle of two entirely different materials: a highway steel box bridge deck and a paved layer, which is used as anticorrosion and waterproof coating for the steel bridge deck. For our study, electrochemical corrosion and pull strength experiments have been selected for the investigation of the corrosion properties of inorganic zinc rich coating, epoxy zinc rich coating and arc sprayed zinc coating. The adhesive strength between the coatings and the panel, and the effect of the coating corrosion on the shear properties of the paved layers including cast asphalt, thermal asphalt mortar, epoxy asphalt and modified asphalt concrete have been investigated. The results show that the adhesive strength between the coatings and the bridge panel is controlled by the method of pre-processing rust removal. Coating by sandblasting has stronger adhesive strength than coating by shot peening. The results also reveal that shear strength of the paved layer is affected by the corrosion product of zinc coating. The arc sprayed zinc coating has stronger shear strength than zinc rich coatings.

  4. New technologies in the paving process need to be based on "common practice" and operators' heuristics

    NARCIS (Netherlands)

    Huerne, ter Henny; Miller, Seirgei; Dorée, André


    This paper describes an initiative that aims to integrate process mod-eling with the tacit knowledge of site personnel in order to accelerate profes-sionalism and widen the application of technology in the asphalt paving proc-ess. A preparatory study was conducted to gain insight into operational st

  5. MH-53J/M Pave Low III/IV Systems Engineering. Case Study (United States)


    both of which were retrofitted beginning in the early 1990s, facilitated stowage and handling when transporting the PAVE LOW aboard a Lockheed C-5...addition of an Embedded Computer Systems Line Replaceable Unit (LRU) rack to host PL IV-unique LRUs. Software changes included the modification of 10

  6. Paving the way for invasive species: road type and the spread of common ragweed (Ambrosia artemisiifolia). (United States)

    Joly, Martin; Bertrand, Pascale; Gbangou, Roland Y; White, Marie-Catherine; Dubé, Jean; Lavoie, Claude


    Roads function as prime habitats and corridors for invasive plant species. Yet despite the diversity of road types, there is little research on the influence of these types on the spread of invaders. Common ragweed (Ambrosia artemisiifolia), a plant producing large amounts of allergenic pollen, was selected as a species model for examining the impact of road type on the spread of invasive plants. We examined this relationship in an agricultural region of Quebec, Canada. We mapped plant distribution along different road types, and constructed a model of species presence. Common ragweed was found in almost all sampling sites located along regional (97%) and local paved (81%) roads. However, verges of unpaved local roads were rarely (13%) colonized by the plant. A model (53% of variance explained), constructed with only four variables (paved regional roads, paved local roads, recently mown road verges, forest cover), correctly predicted (success rate: 89%) the spatial distribution of common ragweed. Results support the hypothesis that attributes associated with paved roads strongly favour the spread of an opportunistic invasive plant species. Specifically, larger verges and greater disturbance associated with higher traffic volume create propitious conditions for common ragweed. To date, emphasis has been placed on controlling the plant in agricultural fields, even though roadsides are probably a much larger seed source. Strategies for controlling the weed along roads have only focused on major highways, even though the considerable populations along local roads also contribute to the production of pollen. Management prioritizations developed to control common ragweed are thus questionable.

  7. Understanding the hepatitis C virus life cycle paves the way for highly effective therapies

    DEFF Research Database (Denmark)

    Scheel, Troels K H; Rice, Charles M


    More than two decades of intense research has provided a detailed understanding of hepatitis C virus (HCV), which chronically infects 2% of the world's population. This effort has paved the way for the development of antiviral compounds to spare patients from life-threatening liver disease...

  8. Impact of some field factors on inhalation exposure levels to bitumen emissions during road paving operations. (United States)

    Deygout, François; Auburtin, Guy


    Variability in occupational exposure levels to bitumen emissions has been observed during road paving operations. This is due to recurrent field factors impacting the level of exposure experienced by workers during paving. The present study was undertaken in order to quantify the impact of such factors. Pre-identified variables currently encountered in the field were monitored and recorded during paving surveys, and were conducted randomly covering current applications performed by road crews. Multivariate variance analysis and regressions were then used on computerized field data. The statistical investigations were limited due to the relatively small size of the study (36 data). Nevertheless, the particular use of the step-wise regression tool enabled the quantification of the impact of several predictors despite the existing collinearity between variables. The two bitumen organic fractions (particulates and volatiles) are associated with different field factors. The process conditions (machinery used and delivery temperature) have a significant impact on the production of airborne particulates and explain up to 44% of variability. This confirms the outcomes described by previous studies. The influence of the production factors is limited though, and should be complemented by studying factors involving the worker such as work style and the mix of tasks. The residual volatile compounds, being part of the bituminous binder and released during paving operations, control the volatile emissions; 73% of the encountered field variability is explained by the composition of the bitumen batch.

  9. PAVEd for Success: An Evaluation of a Comprehensive Preliteracy Program for Four-Year-Old Children (United States)

    Schwanenflugel, Paula J.; Hamilton, Claire E.; Neuharth-Pritchett, Stacey; Restrepo, M. Adelaida; Bradley, Barbara A.; Webb, Mi-Young


    The purpose of the study was to evaluate the effectiveness of "PAVEd for Success," comprehensive preliteracy program guidelines to support the development of foundational preliteracy skills in 4 year olds. Prekindergarten teachers received professional development on variables of the program that included a summer institute, after-school…

  10. 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

  11. 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


    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang


    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 C. to C. range as well as in excess of 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.

  13. Hierarchical zeolites from class F coal fly ash (United States)

    Chitta, Pallavi

    Fly ash, a coal combustion byproduct is classified as types class C and class F. Class C fly ash is traditionally recycled for concrete applications and Class F fly ash often disposed in landfills. Class F poses an environmental hazard due to disposal and leaching of heavy metals into ground water and is important to be recycled in order to mitigate the environmental challenges. A major recycling option is to reuse the fly ash as a low-cost raw material for the production of crystalline zeolites, which serve as catalysts, detergents and adsorbents in the chemical industry. Most of the prior literature of fly ash conversion to zeolites does not focus on creating high zeolite surface area zeolites specifically with hierarchical pore structure, which are very important properties in developing a heterogeneous catalyst for catalysis applications. This research work aids in the development of an economical process for the synthesis of high surface area hierarchical zeolites from class F coal fly ash. In this work, synthesis of zeolites from fly ash using classic hydrothermal treatment approach and fusion pretreatment approach were examined. The fusion pretreatment method led to higher extent of dissolution of silica from quartz and mullite phases, which in turn led to higher surface area and pore size of the zeolite. A qualitative kinetic model developed here attributes the difference in silica content to Si/Al ratio of the beginning fraction of fly ash. At near ambient crystallization temperatures and longer crystallization times, the zeolite formed is a hierarchical faujasite with high surface area of at least 360 m2/g. This work enables the large scale recycling of class F coal fly ash to produce zeolites and mitigate environmental concerns. Design of experiments was used to predict surface area and pore sizes of zeolites - thus obviating the need for intense experimentation. The hierarchical zeolite catalyst supports tested for CO2 conversion, yielded hydrocarbons

  14. A method for treating bottom ash

    NARCIS (Netherlands)

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


    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


    Institute of Scientific and Technical Information of China (English)


    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.

  16. Artificial cloud test confirms volcanic ash detection using infrared spectral imaging. (United States)

    Prata, A J; Dezitter, F; Davies, I; Weber, K; Birnfeld, M; Moriano, D; Bernardo, C; Vogel, A; Prata, G S; Mather, T A; Thomas, H E; Cammas, J; Weber, M


    Airborne volcanic ash particles are a known hazard to aviation. Currently, there are no means available to detect ash in flight as the particles are too fine (radii ash clouds are difficult or impossible to detect by eye. The economic cost and societal impact of the April/May 2010 Icelandic eruption of Eyjafjallajökull generated renewed interest in finding ways to identify airborne volcanic ash in order to keep airspace open and avoid aircraft groundings. We have designed and built a bi-spectral, fast-sampling, uncooled infrared camera device (AVOID) to examine its ability to detect volcanic ash from commercial jet aircraft at distances of more than 50 km ahead. Here we report results of an experiment conducted over the Atlantic Ocean, off the coast of France, confirming the ability of the device to detect and quantify volcanic ash in an artificial ash cloud created by dispersal of volcanic ash from a second aircraft. A third aircraft was used to measure the ash in situ using optical particle counters. The cloud was composed of very fine ash (mean radii ~10 μm) collected from Iceland immediately after the Eyjafjallajökull eruption and had a vertical thickness of ~200 m, a width of ~2 km and length of between 2 and 12 km. Concentrations of ~200 μg m(-3) were identified by AVOID at distances from ~20 km to ~70 km. For the first time, airborne remote detection of volcanic ash has been successfully demonstrated from a long-range flight test aircraft.

  17. Artificial cloud test confirms volcanic ash detection using infrared spectral imaging (United States)

    Prata, A. J.; Dezitter, F.; Davies, I.; Weber, K.; Birnfeld, M.; Moriano, D.; Bernardo, C.; Vogel, A.; Prata, G. S.; Mather, T. A.; Thomas, H. E.; Cammas, J.; Weber, M.


    Airborne volcanic ash particles are a known hazard to aviation. Currently, there are no means available to detect ash in flight as the particles are too fine (radii < 30 μm) for on-board radar detection and, even in good visibility, ash clouds are difficult or impossible to detect by eye. The economic cost and societal impact of the April/May 2010 Icelandic eruption of Eyjafjallajökull generated renewed interest in finding ways to identify airborne volcanic ash in order to keep airspace open and avoid aircraft groundings. We have designed and built a bi-spectral, fast-sampling, uncooled infrared camera device (AVOID) to examine its ability to detect volcanic ash from commercial jet aircraft at distances of more than 50 km ahead. Here we report results of an experiment conducted over the Atlantic Ocean, off the coast of France, confirming the ability of the device to detect and quantify volcanic ash in an artificial ash cloud created by dispersal of volcanic ash from a second aircraft. A third aircraft was used to measure the ash in situ using optical particle counters. The cloud was composed of very fine ash (mean radii ~10 μm) collected from Iceland immediately after the Eyjafjallajökull eruption and had a vertical thickness of ~200 m, a width of ~2 km and length of between 2 and 12 km. Concentrations of ~200 μg m-3 were identified by AVOID at distances from ~20 km to ~70 km. For the first time, airborne remote detection of volcanic ash has been successfully demonstrated from a long-range flight test aircraft.

  18. Knowledge Transfer from the Forestry Sector to the Agricultural Sector concerning Ash Recycling; Kunskapsoeverfoering fraan skogssektorn till jordbrukssektorn angaaende askaaterfoering

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Johanna; Salomon, Eva


    Cultivation of energy crops on arable land is increasing in Sweden. More than half these crops can be used for combustion, increasing the amount of ash that can be recycled to arable land. Ash is an interesting agricultural fertiliser, but more knowledge is needed before it can be applied and handled in a controlled way. Knowledge and experience concerning recycling of ash within the forest sector can be transferred to the agricultural sector. This project examined ways for ash producers to ensure safe long-term disposal of ash and to improve plant nutrient recycling. The overall aims were to identify experiences and knowledge within forestry that could be applied in agriculture; to identify gaps in knowledge and research requirements regarding ash recycling to arable land; and to produce recommendations on how to increase ash recycling. Literature describing the conditions for ash application to arable land and existing knowledge about ash recycling to forestry were reviewed. Nutrient balances were drawn up for phosphorus, cadmium, zinc and copper, which are relevant in biofuel ash recycling to agriculture. Data on ash application, mainly on forest land, were collected through telephone interviews. For ash to be more attractive for farmers, the ash product must be a realistic alternative to artificial fertilisers. Research and demonstration projects are needed to study the effects of ash on yield and quality in different crops. Different biofuel ash products have differing qualities and can thus have different fields of application within agriculture and can be applied in varying amounts. For example, clean straw ash has a low P and Cd content and mainly supplies potassium and lime. The balance calculations showed that the highest quality ash for arable land is bottom ash from grate combustion of forest trash with 2-5 % of willow. There are both differences and similarities between ash application in agriculture and forestry. An important feature is the

  19. ICT Demonstration

    DEFF Research Database (Denmark)

    Jensen, Tine Wirenfeldt; Bay, Gina

    In this demonstration we present and discuss two interrelated on-line learning resources aimed at supporting international students at Danish universities in building study skills (the Study Metro) and avoiding plagiarism (Stopplagiarism). We emphasize the necessity of designing online learning r...

  20. Tested Demonstrations. (United States)

    Gilbert, George L., Ed.


    Describes two demonstrations to illustrate characteristics of substances. Outlines a method to detect the changes in pH levels during the electrolysis of water. Uses water pistols, one filled with methane gas and the other filled with water, to illustrate the differences in these two substances. (TW)

  1. 1999 international ash utilization symposium

    Energy Technology Data Exchange (ETDEWEB)



    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'.

  2. Radioactivity of wood ash; Puun tuhkan radioaktiivisuus

    Energy Technology Data Exchange (ETDEWEB)

    Rantavaara, A.; Moring, M


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

  3. Permeation Properties and Pore Structure of Surface Layer of Fly Ash Concrete

    Directory of Open Access Journals (Sweden)

    Jun Liu


    Full Text Available This paper presents an experimental study on the nature of permeation properties and pore structure of concrete surface layers containing fly ash. Concretes containing different dosages of fly ash as a replacement for cement (15% and 30% by weight of total cement materials, respectively were investigated. Concrete without any fly ash added was also employed as the reference specimen. Laboratory tests were conducted to determine the surface layer properties of concrete including chloride transport, apparent water permeability and pore structure. The results demonstrate that incorporation of fly ash, for the early test period, promotes the chloride ingress at the surface layer of concrete but substituting proportions of fly ash may have little impact on it. With the process of chloride immersion, the chloride concentration at the surface layer of concrete with or without fly ash was found to be nearly the same. In addition, it is suggested that the water permeability at the concrete surface area is closely related to the fly ash contents as well as the chloride exposure time. Pore structure was characterized by means of mercury intrusion porosimetry (MIP test and the scanning electron microscopy (SEM images. The modification of pore structure of concrete submersed in distilled water is determined by the pozzolanic reaction of fly ash and the calcium leaching effect. The pozzolanic reaction was more dominant at the immersion time of 180 days while the calcium leaching effect became more evident after 270 days.

  4. Use of Incineration MSW Ash: A Review

    Directory of Open Access Journals (Sweden)

    Charles H. K. Lam


    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. Radon emanation fractions from concretes containing fly ash and metakaolin

    Energy Technology Data Exchange (ETDEWEB)

    Taylor-Lange, Sarah C., E-mail: [Department of Civil, Architectural, and Environmental Engineering, 1 University Station C1748, The University of Texas at Austin, Austin, TX 78712 (United States); Juenger, Maria C.G. [Department of Civil, Architectural, and Environmental Engineering, 1 University Station C1748, The University of Texas at Austin, Austin, TX 78712 (United States); Siegel, Jeffrey A. [Department of Civil, Architectural, and Environmental Engineering, 1 University Station C1748, The University of Texas at Austin, Austin, TX 78712 (United States); Department of Civil Engineering, 35 St. George Street, University of Toronto, Toronto, ON, M5S 1A4 (Canada)


    Radon ({sup 222}Rn) and progenies emanate from soil and building components and can create an indoor air quality hazard. In this study, nine concrete constituents, including the supplementary cementitious materials (SCMs) fly ash and metakaolin, were used to create eleven different concrete mixtures. We investigated the effect of constituent radium specific activity, radon effective activity and emanation fraction on the concrete emanation fraction and the radon exhalation rate. Given the serious health effects associated with radionuclide exposure, experimental results were coupled with Monte Carlo simulations to demonstrate predictive differences in the indoor radon concentration due to concrete mixture design. The results from this study show that, on average, fly ash constituents possessed radium specific activities ranging from 100 Bq/kg to 200 Bq/kg and emanation fractions ranging from 1.1% to 2.5%. The lowest emitting concrete mixture containing fly ash resulted in a 3.4% reduction in the concrete emanation fraction, owing to the relatively low emanation that exists when fly ash is part of concrete. On average, the metakaolin constituents contained radium specific activities ranging from 67 Bq/kg to 600 Bq/kg and emanation fractions ranging from 8.4% to 15.5%, and changed the total concrete emanation fraction by roughly ± 5% relative to control samples. The results from this study suggest that SCMs can reduce indoor radon exposure from concrete, contingent upon SCM radionucleotide content and emanation fraction. Lastly, the experimental results provide SCM-specific concrete emanation fractions for indoor radon exposure modeling. - Highlights: • Fly ash or metakaolin SCMs can neutralize or reduce concrete emanation fractions. • The specific activity of constituents is a poor predictor of the concrete emanation fraction. • Exhalation from fly ash concretes represents a small fraction of the total indoor radon concentration.

  6. Identifying glass compositions in fly ash

    Directory of Open Access Journals (Sweden)

    Katherine eAughenbaugh


    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.

  7. Potential of used frying oil in paving material: solution to environmental pollution problem. (United States)

    Singh-Ackbarali, Dimple; Maharaj, Rean; Mohamed, Nazim; Ramjattan-Harry, Vitra


    The improper disposal of used frying oil (UFO) presents numerous ecological, environmental and municipal problems. Of great concern is the resultant blockage of municipal drainage systems and water treatment facilities, harm to wildlife when they become coated in it and detriment to aquatic life and ecosystems due to the depletion of the oxygen content in water bodies such as rivers and lakes that have become contaminated. Statistics show that in Trinidad and Tobago, in excess of one million liters of used cooking oil is collected annually from various restaurant chains. This paper investigated the potential of using UFO as a performance enhancing additive for road paving applications utilizing Trinidad Lake Asphalt (TLA) and Trinidad Petroleum Bitumen (TPB) as a mitigation strategy for improper UFO disposal. Modified blends containing various additions of UFO (2-10% wt) were prepared for the TLA and TPB asphaltic binders. Results demonstrated in terms of stiffness, increasing the dosage of UFO in TLA and TPB base binders resulted in a gradual decrease in stiffness (G* value decreased). In terms of elasticity, increasing the dosage of the UFO additive in TLA resulted in a general decrease in the elasticity of the blends indicated by an increase in phase angle or phase lag (δ). Increasing dosages of the UFO additive in TPB resulted in a significant decrease in δ where the most elastic blend was at the 6% UFO level. TLA and UFO-TLA modified blends exhibited significantly lower values of δ and higher values of G* confirming the superiority of the TLA material. Incorporation of the UFO in the blends led to a decrease in the rutting resistance and increase in the fatigue cracking resistance (decrease in G*/sinδ and G*sinδ, respectively). This study highlighted the potential for the reuse of UFO as an asphalt modifier capable of producing customized UFO modified asphaltic blends for special applications and confirms its feasibility as an environmentally attractive

  8. Interspecific variation in resistance to emerald ash borer (Coleoptera: Buprestidae) among North American and Asian ash (Fraxinus spp.). (United States)

    Rebek, Eric J; Herms, Daniel A; Smitley, David R


    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.

  9. In situ coronary stent paving by Pluronic F127-alginate gel blends: Formulation and erosion tests. (United States)

    Dalmoro, Annalisa; Barba, Anna Angela; Grassi, Mario; Grassi, Gabriele; Lamberti, Gaetano


    In this work the development of an experimental protocol to perform the in situ gel-paving of coronary stent is presented. Biocompatible aqueous blends of Pluronic F127 and sodium alginates are used as potential drug dosage system for pharmacological in situ treatment of coronary in-stent restenosis. Pluronic F127/alginate aqueous blend has the unique characteristic to be liquid at room condition and to form gel at physiological temperature. The proposed protocol is based on the blend injection on stent wall previously implanted in a flexible silicon pipe mimicking the coronary artery. Injected blend is warmed up until human body temperature achieving a soft gel, then it is reticulated by copper bivalent ions to obtain an hard gel. To test the gel paving resistance to erosion phenomena when it is exposed to fluid flux (i.e. blood flux) a dedicated device, (the Simulated Artery Device, SAD), was built to simulate the human circulatory apparatus. The SAD is an hydraulic circuit in which a buffer solution (at pH 7.4) was fluxed by a peristaltic pump through the pipe hosting the covered stent. Erosion tests were performed monitoring, by gravimetric and spectrophotometric methods, the residual mass anchored to stent mesh after given times. The obtained results showed that the in situ gel-paving developed protocol was efficacious and reliable. The gel-paving was completely eroded in a time of the same order of magnitude of the physiological period required to restore the coronary lesion (subsequent to the atheroma removal) and of a pharmacological therapy to inhibit the in-stent-restenosis pathology. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1013-1022, 2016.

  10. Natural weathering in dry disposed ash dump: Insight from chemical, mineralogical and geochemical analysis of fresh and unsaturated drilled cores. (United States)

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


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


    Directory of Open Access Journals (Sweden)

    Ganjar Samudro


    Full Text Available Lumpur Lapindo (LL atau Lumpur Sidoarjo (Lusi merupakan lumpur panas, yang pemanfaatannya sangat terbatas dan menimbulkan dampak sosial dan lingkungan yang cukup besar. Karakteristik Lumpur Lapindo mengandung silikat (SiO2 dan kapur (CaO yang cukup tinggi dan bersifat pozoland. Selain kandungan kimia yang menguntungkan, Lumpur Lapindo juga bersifat B3 dengan kandungan logam berat Pb 35,41 ppm dan Cu 21,9 ppm yang melebihi baku mutu Kepmenkes no.907/2002, PP no.82/2001 dan PP no.18/1999. Teknik olidifikasi menjadi paving block dapat digunakan untuk mengubah watak fisik dan kimia limbah B3 dengan cara penambahan senyawa pengikat sehingga pergerakan senyawa-senyawa B3 dapat dihambat dan membentuk ikatan massa monolit dengan struktur yang kekar. Penambahan Lumpur Lapindo sebagai substitusi semen dan pasir ditentukan sebesar 10%, 20%, 30%, 40%, dan 50%, dengan pengujian terhadap kuat tekan, daya serap air dan perlindian. Penelitian ini didapatkan variasi Lumpur Lapindo sebagai substitusi pasir dan semen optimum asingmasing sebesar 30% dengan kuat tekan 408 kg/cm2 , daya serap air 10,17% dan uji perlindian dihasilkan dibawah 0,03 ppm Pb dan Cu, serta biaya pembuatan 1 buah paving block berkurang dari Rp 1.302,86 per buah menjadi Rp 1.059,40 per buah. Lumpur Lapindo sebagai substitusi semen lebih baik penggunaannya dalam pembuatan paving block ramah ingkungan.

  12. Fly ash application in nutrient poor agriculture soils: impact on methanotrophs population dynamics and paddy yields. (United States)

    Singh, Jay Shankar; Pandey, Vimal Chandra


    There are reports that the application of fly ash, compost and press mud or a combination thereof, improves plant growth, soil microbial communities etc. Also, fly ash in combination with farmyard manure or other organic amendments improves soil physico-chemical characteristics, rice yield and microbial processes in paddy fields. However, the knowledge about the impact of fly ash inputs alone or in combination with other organic amendments on soil methanotrophs number in paddy soils is almost lacking. We hypothesized that fly ash application at lower doses in paddy agriculture soil could be a potential amendment to elevate the paddy yields and methanotrophs number. Here we demonstrate the impact of fly ash and press mud inputs on number of methanotrophs, antioxidants, antioxidative enzymatic activities and paddy yields at agriculture farm. The impact of amendments was significant for methanotrophs number, heavy metal concentration, antioxidant contents, antioxidant enzymatic activities and paddy yields. A negative correlation was existed between higher doses of fly ash-treatments and methanotrophs number (R(2)=0.833). The content of antioxidants and enzymatic activities in leaves of higher doses fly ash-treated rice plants increased in response to stresses due to heavy metal toxicity, which was negatively correlated with rice grain yield (R(2)=0.944) and paddy straw yield (R(2)=0.934). A positive correlation was noted between heavy metals concentrations and different antioxidant and enzymatic activities across different fly ash treated plots.The data of this study indicate that heavy metal toxicity of fly ash may cause oxidative stress in the paddy crop and the antioxidants and related enzymes could play a defensive role against phytotoxic damages. We concluded that fly ash at lower doses with press mud seems to offer the potential amendments to improving soil methanotrophs population and paddy crop yields for the nutrient poor agriculture soils.

  13. Back from the Ashes

    Institute of Scientific and Technical Information of China (English)


    OCTOBER 18,1998. Paris. A 1,800-strong audience packedthemselves into the 1,492-seat capacityof the Le Notre Hall of the Louvre. TheDawn of the Chinese Nation—Ancientand Modern Fashion Show was in fullswing. 123 suits demonstrated the 4,000-year-old culture of Chinese costume andaccessories. The fantasy show by 30Chinese models and three French modelsenthralled the onlookers. The French Prime Minister, Vedrine,came to the show and told the reporter:"Chinese garments are really beautiful. I

  14. Fundamental study of ash formation and deposition: Effect of reducing stoichiometry

    Energy Technology Data Exchange (ETDEWEB)

    Helble, J.J.; Bool, L.E.; Kang, S.G. [and others


    This project is designed to examine the effects of combustion stoichiometry on the fundamental aspects of ash formation and ash deposit initiation. Emphasis is being placed on reducing stoichiometries associated with low-NOx combustion, although a range of oxidant/fuel ratios are being considered. Previous work has demonstrated that ash formation depends strongly upon coal mineralogy, including mineral type, size, amount, and the presence of organically associated inorganic species. Combustion temperature and the oxidation state of iron also play a significant role. As these latter items will vary with changes in stoichiometry, research to determine the net effect on deposition is required.

  15. Utilization Of Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    S. D. Nagrale


    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.

  16. The Ashes of Marci Shore

    Directory of Open Access Journals (Sweden)

    Zbigniew Kopeć


    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.

  17. GASIS demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Vidas, E.H. [Energy and Environmental Analysis, Inc., Arlington, VA (United States)


    A prototype of the GASIS database and retrieval software has been developed and is the subject of this poster session and computer demonstration. The prototype consists of test or preliminary versions of the GASIS Reservoir Data System and Source Directory datasets and the software for query and retrieval. The prototype reservoir database covers the Rocky Mountain region and contains the full GASIS data matrix (all GASIS data elements) that will eventually be included on the CD-ROM. It is populated for development purposes primarily by the information included in the Rocky Mountain Gas Atlas. The software has been developed specifically for GASIS using Foxpro for Windows. The application is an executable file that does not require Foxpro to run. The reservoir database software includes query and retrieval, screen display, report generation, and data export functions. Basic queries by state, basin, or field name will be assisted by scrolling selection lists. A detailed query screen will allow record selection on the basis of any data field, such as depth, cumulative production, or geological age. Logical operators can be applied to any-numeric data element or combination of elements. Screen display includes a {open_quotes}browse{close_quotes} display with one record per row and a detailed single record display. Datasets can be exported in standard formats for manipulation with other software packages. The Source Directory software will allow record retrieval by database type or subject area.

  18. Vitrification of municipal solid waste incineration fly ash using biomass ash as additives. (United States)

    Alhadj-Mallah, Moussa-Mallaye; Huang, Qunxing; Cai, Xu; Chi, Yong; Yan, JianHua


    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.

  19. 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


    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.

  20. BNL Citric Acid Technology: Pilot Scale Demonstration

    Energy Technology Data Exchange (ETDEWEB)



    The objective of this project is to remove toxic metals such as lead and cadmium from incinerator ash using the Citric Acid Process developed at Brookhaven National Laboratory. In this process toxic metals in bottom ash from the incineration of municipal solid waste were first extracted with citric acid followed by biodegradation of the citric acid-metal extract by the bacterium Pseudomonas fluorescens for metals recovery. The ash contained the following metals: Al, As, Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Se, Sr, Ti, and Zn. Optimization of the Citric Acid Process parameters which included citric acid molarity, contact time, the impact of mixing aggressiveness during extraction and pretreatment showed lead and cadmium removal from incinerator ash of >90%. Seeding the treated ash with P. fluorescens resulted in the removal of residual citric acid and biostabilization of any leachable lead, thus allowing it to pass EPA?s Toxicity Characteristic Leaching Procedure. Biodegradation of the citric acid extract removed >99% of the lead from the extract as well as other metals such as Al, Ca, Cu, Fe, Mg, Mn, Ti, and Zn. Speciation of the bioprecipitated lead by Extended X-ray Absorption Fine Structure at the National Synchrotron Light Source showed that the lead is predominantly associated with the phosphate and carboxyl functional groups in a stable form. Citric acid was completely recovered (>99%) from the extract by sulfide precipitation technique and the extraction efficiency of recovered citric acid is similar to that of the fresh citric acid. Recycling of the citric acid should result in considerable savings in the overall treatment cost. We have shown the potential application of this technology to remove and recover the metal contaminants from incinerator ash as well as from other heavy metal bearing wastes (i.e., electric arc furnace dust from steel industry) or soils. Information developed from this project is being applied to demonstrate the remediation of

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


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


    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...

  2. Hail formation triggers rapid ash aggregation in volcanic plumes (United States)

    Van Eaton, Alexa; Mastin, Larry G.; Herzog, M.; Schwaiger, Hans F.; Schneider, David J.; Wallace, Kristi; Clarke, Amanda B


    During explosive eruptions, airborne particles collide and stick together, accelerating the fallout of volcanic ash and climate-forcing aerosols. This aggregation process remains a major source of uncertainty both in ash dispersal forecasting and interpretation of eruptions from the geological record. Here we illuminate the mechanisms and timescales of particle aggregation from a well-characterized ‘wet’ eruption. The 2009 eruption of Redoubt Volcano in Alaska incorporated water from the surface (in this case, a glacier), which is a common occurrence during explosive volcanism worldwide. Observations from C-band weather radar, fall deposits, and numerical modeling demonstrate that volcanic hail formed rapidly in the eruption plume, leading to mixed-phase aggregation of ~95% of the fine ash and stripping much of the cloud out of the atmosphere within 30 minutes. Based on these findings, we propose a mechanism of hail-like aggregation that contributes to the anomalously rapid fallout of fine ash and the occurrence of concentrically-layered aggregates in volcanic deposits.

  3. Volcanic ash infrared signature: porous non-spherical ash particle shapes compared to homogeneous spherical ash particles (United States)

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


    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.

  4. As and Se interactions with fly ashes

    Directory of Open Access Journals (Sweden)

    M. Díaz-Somoano


    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.

  5. Effect of ferrous metal presence on lead leaching in municipal waste incineration bottom ashes. (United States)

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


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

  6. Volcanic ash at Santiaguito dome complex, Guatemala (United States)

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


    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.

  7. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

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


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

  8. 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


    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.

  9. 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)


    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

  10. Strong responses of Southern Ocean phytoplankton communities to volcanic ash


    Browning, T.J.; Bouman, H. A.; Henderson, G. M.; Mather, T.A.; D. M. Pyle; Schlosser, Christian; Woodward, E.M.S.; Moore, C. M.


    Volcanic eruptions have been hypothesized as an iron supply mechanism for phytoplankton blooms; however, little direct evidence of stimulatory responses has been obtained in the field. Here we present the results of twenty-one 1-2day bottle enrichment experiments from cruises in the South Atlantic and Southern Ocean which conclusively demonstrated a photophysiological and biomass stimulation of phytoplankton communities following supply of basaltic or rhyolitic volcanic ash. Furthermore, expe...

  11. 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.


    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.)

  12. Treatment of fly ash for use in concrete (United States)

    Boxley, Chett [Park City, UT


    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.

  13. 10 Risk to Ash from Emerald Ash Borer: Can Biological Control Prevent the Loss of Ash Stands (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. Characteristics of spanish fly ashes

    Directory of Open Access Journals (Sweden)

    de Luxán, M. P.


    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.

  15. Volcanic ash supports a diverse bacterial community in a marine mesocosm (United States)

    Verena Witt,; Paul M Ayris,; Damby, David; Corrado Cimarelli,; Ulrich Kueppers,; Donald B Dingwell,; Gert Wörheide,


    Shallow-water coral reef ecosystems, particularly those already impaired by anthropogenic pressures, may be highly sensitive to disturbances from natural catastrophic events, such as volcanic eruptions. Explosive volcanic eruptions expel large quantities of silicate ash particles into the atmosphere, which can disperse across millions of square kilometres and deposit into coral reef ecosystems. Following heavy ash deposition, mass mortality of reef biota is expected, but little is known about the recovery of post-burial reef ecosystems. Reef regeneration depends partly upon the capacity of the ash deposit to be colonised by waterborne bacterial communities and may be influenced to an unknown extent by the physiochemical properties of the ash substrate itself. To determine the potential for volcanic ash to support pioneer bacterial colonisation, we exposed five well-characterised volcanic and coral reef substrates to a marine aquarium under low light conditions for 3 months: volcanic ash, synthetic volcanic glass, carbonate reef sand, calcite sand and quartz sand. Multivariate statistical analysis of Automated Ribosomal Intergenic Spacer Analysis (ARISA) fingerprinting data demonstrates clear segregation of volcanic substrates from the quartz and coral reef substrates over 3 months of bacterial colonisation. Overall bacterial diversity showed shared and substrate-specific bacterial communities; however, the volcanic ash substrate supported the most diverse bacterial community. These data suggest a significant influence of substrate properties (composition, granulometry and colour) on bacterial settlement. Our findings provide first insights into physicochemical controls on pioneer bacterial colonisation of volcanic ash and highlight the potential for volcanic ash deposits to support bacterial diversity in the aftermath of reef burial, on timescales that could permit cascading effects on larval settlement.

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  17. Electrodialytic removal of heavy metals from fly ashes

    DEFF Research Database (Denmark)

    Pedersen, Anne Juul


    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....

  18. 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


    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.

  19. Triboelectric charging of volcanic ash from the 2011 Gr\\'{i}msv\\"{o}tn eruption

    CERN Document Server

    Houghton, Isobel M P; Nicoll, Keri A


    Triboelectric charging of different size fractions of a sample of volcanic ash is studied experimentally. Laboratory experiments demonstrate that the normalised span of the particle size distribution plays an important role in the magnitude of charging generated. Previous measurements of the volcanic plumes have shown that ash particles are electrically charged up to hundreds of km away from the vent, which indicates the the ash particles continue to be charged in the plume through the mechanism of triboelectrification [Harrison et al., Env. Res. Lett. 5 024004 (2010), Hatakeyama J. Met. Soc. Japan 27 372 (1949)]. The influence of the normalised span on plume charging suggests that all ash plumes are likely to be charged, with implications for remote sensing and plume lifetime.


    Directory of Open Access Journals (Sweden)

    Ravinder Pal Singh


    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.

  1. Using Drainage Slots in Permeable Paving Blocks to Delay the Effects of Clogging: Proof of Concept Study

    Directory of Open Access Journals (Sweden)

    Terry Lucke


    Full Text Available Permeable interlocking concrete pavements (PICP are specifically designed to remove sediment and other pollutants from stormwater runoff. Over time, this can lead to clogging of the PICP system. Previous research has shown that much of the clogging occurs on the bedding aggregate directly below the paving joints, while the remainder of the aggregate is unaffected. This paper describes a proof of concept study to delay the effects of clogging by making more efficient use of the bedding aggregate used in PICP systems. Lateral drainage slots were cut into the underside of PICP blocks to allow sediment-laden stormwater to access, and be filtered by, a greater surface area of bedding aggregate. Eight different slot designs were trialed in the study to determine which of the slot designs made the most efficient use of the bedding aggregate to filter the sediment from the stormwater. The study results demonstrated that the eight drainage slot designs deposited between 25% and 366% more sediment (by weight beneath the pavers than the control pavement. The results of the study suggest that PICP systems with drainage slots cast into their bases would take much longer to clog than unmodified pavers, thereby proving the concept of this study.

  2. Column leaching from biomass combustion ashes

    DEFF Research Database (Denmark)

    Maresca, Alberto; Astrup, Thomas Fruergaard


    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...

  3. 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


    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.

  4. Wet physical separation of MSWI bottom ash

    NARCIS (Netherlands)

    Muchova, L.


    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),

  5. 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.


    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.

  6. 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.


    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)

  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)


    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. Polymeric endoaortic paving: Mechanical, thermoforming, and degradation properties of polycaprolactone/polyurethane blends for cardiovascular applications. (United States)

    Ashton, J H; Mertz, J A M; Harper, J L; Slepian, M J; Mills, J L; McGrath, D V; Vande Geest, J P


    Polymeric endoaortic paving (PEAP) is a process by which a polymer is endovascularly delivered and thermoformed to coat or "pave" the lumen of the aorta. This method may offer an improvement to conventional endoaortic therapy in allowing conformal graft application with reduced risk of endoleak and customization to complex patient geometries. Polycaprolactone (PCL)/polyurethane (PU) blends of various blend ratios were assessed as a potential material for PEAP by characterizing their mechanical, thermoforming and degradation properties. Biaxial tension testing revealed that the blends' stiffness is similar to that of aortic tissue, is higher for blends with more PCL content, and may be affected by thermoforming and degradation. Tubes of blends were able to maintain a higher diameter increase after thermoforming at higher PCL content and higher heating temperatures; 50/50 blend tubes heated to 55 °C were able to maintain 90% of the diameter increase applied. Delamination forces of the blends ranged from 41 to 235 N m⁻². In a Pseudomonas lipase solution, the 50/50 blend had a 94% lower degradation rate than pure PCL, and the 10/90 blend exhibited no degradation. These results indicate that PEAP, consisting of a PCL/PU blend, may be useful in developing the next generation of endoaortic therapy.


    Directory of Open Access Journals (Sweden)

    J. Choi


    Full Text Available In the current study, we developed a methodology for detecting cracks in the surface of paved road using 3D digital surface model of road created by measuring with three-dimensional laser scanner which works on the basis of the light-section method automatically. For the detection of cracks from the imagery data of the model, the background subtraction method (Rolling Ball Background Subtraction Algorithm was applied to the data for filtering out the background noise originating from the undulation and gradual slope and also for filtering the ruts that were caused by wearing, aging and excessive use of road and other reasons. We confirmed the influence from the difference in height (depth caused by forgoing reasons included in a data can be reduced significantly at this stage. Various parameters of ball radius were applied for checking how the result of data obtained with this process vary according to the change of parameter and it becomes clear that there are not important differences by the change of parameters if they are in a certain range radius. And then, image segmentation was performed by multi-resolution segmentation based on the object-based image analysis technique. The parameters for the image segmentation, scale, pixel value (height/depth and the compactness of objects were used. For the classification of cracks in the database, the height, length and other geometric property are used and we confirmed the method is useful for the detection of cracks in a paved road surface.

  10. Detection of Cracks in Paved Road Surface Using Laser Scan Image Data (United States)

    Choi, J.; Zhu, L.; Kurosu, H.


    In the current study, we developed a methodology for detecting cracks in the surface of paved road using 3D digital surface model of road created by measuring with three-dimensional laser scanner which works on the basis of the light-section method automatically. For the detection of cracks from the imagery data of the model, the background subtraction method (Rolling Ball Background Subtraction Algorithm) was applied to the data for filtering out the background noise originating from the undulation and gradual slope and also for filtering the ruts that were caused by wearing, aging and excessive use of road and other reasons. We confirmed the influence from the difference in height (depth) caused by forgoing reasons included in a data can be reduced significantly at this stage. Various parameters of ball radius were applied for checking how the result of data obtained with this process vary according to the change of parameter and it becomes clear that there are not important differences by the change of parameters if they are in a certain range radius. And then, image segmentation was performed by multi-resolution segmentation based on the object-based image analysis technique. The parameters for the image segmentation, scale, pixel value (height/depth) and the compactness of objects were used. For the classification of cracks in the database, the height, length and other geometric property are used and we confirmed the method is useful for the detection of cracks in a paved road surface.

  11. Investigation on Leaching Behaviour of Fly Ash and Bottom Ash Replacement in Self-Compacting Concrete (United States)

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


    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.

  12. Construction procedures using self hardening fly ash (United States)

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


    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.

  13. Geopolymerisation of fly ashes with waste aluminium anodising etching solutions. (United States)

    Ogundiran, M B; Nugteren, H W; Witkamp, G J


    Combined management of coal combustion fly ash and waste aluminium anodising etching solutions using geopolymerisation presents economic and environmental benefits. The possibility of using waste aluminium anodising etching solution (AES) as activator to produce fly ash geopolymers in place of the commonly used silicate solutions was explored in this study. Geopolymerisation capacities of five European fly ashes with AES and the leaching of elements from their corresponding geopolymers were studied. Conventional commercial potassium silicate activator-based geopolymers were used as a reference. The geopolymers produced were subjected to physical, mechanical and leaching tests. The leaching of elements was tested on 28 days cured and crushed geopolymers using NEN 12457-4, NEN 7375, SPLP and TCLP leaching tests. After 28 days ambient curing, the geopolymers based on the etching solution activator showed compressive strength values between 51 and 84 MPa, whereas the commercial potassium silicate based geopolymers gave compressive strength values between 89 and 115 MPa. Based on the regulatory limits currently associated with the used leaching tests, all except one of the produced geopolymers (with above threshold leaching of As and Se) passed the recommended limits. The AES-geopolymer geopolymers demonstrated excellent compressive strength, although less than geopolymers made from commercial activator. Additionally, they demonstrated low element leaching potentials and therefore can be suitable for use in construction works.

  14. Ashes 2013 - A network theory analysis of Cricket strategies

    CERN Document Server

    Mukherjee, Satyam


    We demonstrate in this paper the use of tools of complex network theory to describe the strategy of Australia and England in the recently concluded Ashes 2013 Test series. Using partnership data made available by cricinfo during the Ashes 2013 Test series, we generate batting partnership network (BPN) for each team, in which nodes correspond to batsmen and links represent runs scored in partnerships between batsmen. The resulting network display a visual summary of the pattern of run-scoring by each team, which helps us in identifying potential weakness in a batting order. We use different centrality scores to quantify the performance, relative importance and effect of removing a player from the team. We observe that England is an extremely well connected team, in which lower order batsmen consistently contributed significantly to the team score. Contrary to this Australia showed dependence on their top order batsmen.

  15. Laboratory Studies of Ice Nucleation on Volcanic Ash (United States)

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


    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.

  16. Treatment of fly ash for use in concrete (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang


    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.

  17. Treatment of fly ash for use in concrete (United States)

    Boxley, Chett; Akash, Akash; Zhao, Qiang


    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.

  18. De-ashing treatment of corn stover improves the efficiencies of enzymatic hydrolysis and consequent ethanol fermentation. (United States)

    He, Yanqing; Fang, Zhenhong; Zhang, Jian; Li, Xinliang; Bao, Jie


    In this study, corn stover with different ash content was pretreated using dry dilute acid pretreatment method at high solids loading of 67% (w/w). The results indicate that the hydrolysis yield of corn stover is increased from 43.30% to 70.99%, and ethanol yield is increased from 51.74% to 73.52% when ash is removed from 9.60% to 4.98%. The pH measurement of corn stover slurry indicates that the decrease of pretreatment efficiency is due to the neutralization of sulfuric acid by alkaline compounds in the ash. The elemental analysis reveals that the ash has the similar composition with the farmland soil. This study demonstrates the importance of ash removal from lignocellulose feedstock under high solids content pretreatment.

  19. Applied investigation on the interaction of hazardous elements binding on ultrafine and nanoparticles in Chinese anthracite-derived fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Luis F.O., E-mail: [Centro Universitario Univates, Programa de Pos Graduacao Ambiente e Desenvolvimento, Rua Avelino Tallini, 171, Universitario, 95900-000 Lajeado, RS (Brazil); Environmental Science and Nanotechnology Department, Catarinense Institute of Environmental Research and Human Development - IPADHC, Capivari de Baixo, Santa Catarina (Brazil); Jasper, Andre [Centro Universitario Univates, Programa de Pos Graduacao Ambiente e Desenvolvimento, Rua Avelino Tallini, 171, Universitario, 95900-000 Lajeado, RS (Brazil); Andrade, Maria L. [Department of Plant Biology and Soil Science, University of Vigo, 36310 Vigo (Spain); Sampaio, Carlos H. [Universidade Federal do Rio Grande do Sul, Escola de Engenharia, Departamento de Metalurgia, Centro de Tecnologia, Av. Bento Goncalves, 9500, Bairro Agronomia, CEP: 91501-970, Porto Alegre, RS (Brazil); Dai, Shifeng; Li, Xiao; Li, Tian; Chen, Weimei; Wang, Xibo; Liu, Huidong; Zhao, Lixin [China University of Mining and Technology, Beijing (China); Hopps, Shelley G.; Jewell, Robert F. [University of Kentucky Center for Applied Energy Research, 2540 Research Park Drive, Lexington, KY 40511 (United States); Hower, James C., E-mail: [University of Kentucky Center for Applied Energy Research, 2540 Research Park Drive, Lexington, KY 40511 (United States)


    A multifaceted instrumental approach was employed to determine the chemistry and mineralogy of pulverized-coal-combustion fly ashes from two Chinese power plants. Techniques included traditional optical microscopy, X-ray diffraction, and chemical analysis along with a variety of electron beam methods. The aim is to demonstrate and bring together the wide variety of procedures dealing with F as the key element of concern, and determining its location in the mineral nanoparticles. The Hg content of the Anwen (Songzao coalfield) fly ashes is higher than that of the Diandong (East Yunnan) fly ashes, possibly owing to the greater C and Cl in the Anwen fly ashes. Both fly ash sources contain a variety of amorphous and nano-crystalline trace-element-bearing particles, both associated with multi-walled carbon nanotubes and as particles independent of carbons.

  20. Impact strength and abrasion resistance of high strength concrete with rice husk ash and rubber tires

    Directory of Open Access Journals (Sweden)

    M. B. Barbosa

    Full Text Available The paper discusses the application of High Strength Concrete (HSC technology for concrete production with the incorporation of Rice Husk Ash (RHA residues by replacing a bulk of the material caking and rubber tires with partial aggregate volume, assessing their influence on the mechanical properties and durability. For concrete with RHA and rubber, it was possible to reduce the brittleness by increasing the energy absorbing capacity. With respect to abrasion, the RHA and rubber concretes showed lower mass loss than the concrete without residues, indicating that this material is attractive to be used in paving. It is thus hoped that these residues may represent a technological and ecological alternative for the production of concrete in construction works.

  1. 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


    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.

  2. Risks of toxic ash from artisanal mining of discarded cellphones

    Energy Technology Data Exchange (ETDEWEB)

    Hibbert, Kathleen [School of Social Ecology, University of California, Irvine, CA 92697 (United States); Ogunseitan, Oladele A., E-mail: [School of Social Ecology, University of California, Irvine, CA 92697 (United States); Department of Population Health and Disease Prevention, Program in Public Health, University of California, Irvine, CA 92697 (United States)


    Highlights: • We simulated artisanal incineration of four component categories of cellphones. • We identified metals and organic chemicals in the resulting electronic waste ash. • We used USETox model to demonstrate potential ecotoxicity and human health impacts. • We identify targets for risk reduction for hazardous chemicals in cellphones. - Abstract: The potential environmental and human health impacts of artisanal mining of electronic waste through open incineration were investigated. A market-representative set of cellphones was dismantled into four component categories—batteries, circuit boards, plastics and screens. The components were shredded, sieved and incinerated at 743–818 °C. The concentrations of 17 metals were determined using U.S. EPA methods 6010C (inductively coupled plasma-atomic emission spectrometry; 6020A (inductively coupled plasma-mass spectrometry, or 7471B and 7470A (cold-vapor atomic absorption). EPA Method 8270 (gas chromatography/mass spectrometry) was used to identify polyaromatic hydrocarbon compounds and polybrominated diphenyl ethers. EPA Method 8082A was used to measure polychlorinated biphenyls and EPA Method 8290 was used for dioxin/furans in the residue ash. The life cycle assessment model USEtox{sup ®} was used to estimate impacts of the ash residue chemicals on human health and the ecosystem. Among metals, copper in printed circuit boards had the highest ecotoxicity impact (1610–1930 PAF m{sup 3}/kg); Beryllium in plastics had the highest impact on producing non-cancer diseases (0.14–0.44 cases/kg of ash); and Nickel had the largest impact on producing cancers (0.093–0.35 cases/kg of ash). Among organic chemicals, dioxins from incinerated batteries produced the largest ecotoxicological impact (1.07E − 04 to 3.64E − 04 PAF m{sup 3}/kg). Furans in incinerated batteries can generate the largest number of cancers and non-cancer diseases, representing 8.12E − 09 to 2.28E − 08 and 8.96E − 10 and 2.52E

  3. Clean Coal Diesel Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Robert Wilson


    A Clean Coal Diesel project was undertaken to demonstrate a new Clean Coal Technology that offers technical, economic and environmental advantages over conventional power generating methods. This innovative technology (developed to the prototype stage in an earlier DOE project completed in 1992) enables utilization of pre-processed clean coal fuel in large-bore, medium-speed, diesel engines. The diesel engines are conventional modern engines in many respects, except they are specially fitted with hardened parts to be compatible with the traces of abrasive ash in the coal-slurry fuel. Industrial and Municipal power generating applications in the 10 to 100 megawatt size range are the target applications. There are hundreds of such reciprocating engine power-plants operating throughout the world today on natural gas and/or heavy fuel oil.

  4. 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)


    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.)

  5. 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


    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.

  6. Evaluation of the relationship between PAH content and mutagenic activity of fumes from roofing and paving asphalts and coal tar pitch. (United States)

    Machado, M L; Beatty, P W; Fetzer, J C; Glickman, A H; McGinnis, E L


    Fume condensates from asphalt and coal tar pitch were evaluated to determine if polycyclic aromatic hydrocarbon (PAH) composition, crude oil source, or temperature at which the fume was generated correlated with mutagenic activity. The fume condensates were tested for mutagenic activity using a modified Ames Test. Benzo[a]pyrene (BP) and other PAHs were detected in all samples. The concentration of BP in coal tar pitch was 18,100 ppm while the concentration in asphalt was less than 6 ppm. Coal tar fumes contained between two and three orders of magnitude more BP, as well as other PAH species, than asphalt fumes. Coal tar fume condensates were also approximately 100 times more mutagenic than those of asphalt. Generation temperature, crude oil source, and/or process conditions affected the PAH concentrations but not the mutagenicity in roofing asphalt fume condensates. With paving asphalt fumes, PAH content and mutagenicity varied with crude oil source but not with processing conditions; due to limited data, it was not possible to determine the effect of generation temperature. Coal tar pitch fumes generated at 316 degrees C contained significantly higher concentrations of PAHs than those generated at 232 degrees C and the mutagenic activity generally paralleled the PAH content. A subset of the paving asphalts demonstrated good correlation between mutagenicity and three- to seven-ring PAH content. These results indicate that asphalt fumes are far less mutagenic than coal tar fumes. Asphalt fumes differ in their ability to induce mutagenic activity, and, most likely, in their potential carcinogenicity.

  7. Marine mesocosm bacterial colonisation of volcanic ash (United States)

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


    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

  8. Stabilization/solidification of incinerator fly ash for the manufacture of artificial aggregate by cementitious granulation

    Energy Technology Data Exchange (ETDEWEB)

    Colangelo, F.; Cioffi, R. [Univ. Pathenope of Naples (Italy). Dept. of Technology; Montagnaro, F.; Santoro, L. [Univ. Federico 2 of Naples (Italy). Dept. of Chemistry; Di Giacomo, C.; Roncone, A. [Extra Group Co., Citta Sant' Angelo (Italy)


    This paper presented the results of a study in which municipal, hospital, and industrial waste ash from an incineration plant equipped with rotary and stoker furnaces was used in a stabilization/solidification granulation process with cement, lime, and coal fly ash as binder components. The ash from the incineration plant was classified as hazardous. The granulation process was conducted with a range of waste ash mixtures in order to determine the appropriate waste ash percentage for the safe manufacture of artificial aggregates. Waste ash content ranging from 50 to 70 per cent was incorporated within the binding matrix. A 2-step granulation process was then conducted with a pure binder in order to encapsulate the granules from the initial process within an outer shell. The granules obtained from the processes were tested to assess their physico-mechanical and leaching properties. Concrete mixtures were then prepared with some of the artificial aggregates made using the granulation process. Results of the study demonstrated that the granules were suitable for the manufacture of concrete blocks. 19 refs., 8 tabs., 1 fig.

  9. An experimental investigation into the trapping model core pillars with reinforced fly ash composites

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, M.K. [National Inst. of Technology, Rourkela (India); Karanam, U.M. [Indian Inst. of Technology, Kharagpur (India)


    This paper presented details of a study which examined the use of fly ash composite materials for backfilling mine voids in room-and-pillar mining techniques. The study examined the load deformation characteristics of model core pillars confined by wire mesh reinforced fly ash composite materials. Anhydrous chemical-grade lime and gypsum were added in various quantities to class F fly ash samples. The model core pillars were 57 mm in diameter and 200 mm in length. The engineering properties of the model core pillars were then determined using unconfined compressive strength and Brazilian indirect tensile strength tests. The experimental investigations showed that the percentage increases in the strength of the trapped model core pillars varied with the different types of composite materials, and was also influenced by the length of the curing period and the ratio of the annular thickness of the fill area to the model core pillar radius. Results demonstrated that the addition of excess lime to fly ash composites was not beneficial. Maximum strength gains of 14 per cent were achieved with model cores of a cement-sand ratio of 1:2.5 for fly ash composites containing 15 per cent lime and 5 per cent gypsum. It was concluded that suitable fly ash composites reinforced with wire ropes can enhance the strength of the load bearing element and alter the post-peak characteristics of trapped cores.

  10. Biomechanics for inclusive urban design: Effects of tactile paving on older adults' gait when crossing the street. (United States)

    Thies, S B; Kenney, L P J; Howard, D; Nester, C; Ormerod, M; Newton, R; Baker, R; Faruk, M; MacLennan, H


    In light of our ageing population it is important that the urban environment is easily accessible and hence supports older adults' independence. Tactile 'blister' paving was originally designed to provide guidance for visually impaired people at pedestrian crossings. However, as research links irregular surfaces to falls in older adults, such paving may have an adverse effect on older people. We investigated the effects of tactile paving on older adults' gait in a scenario closely resembling crossing the street. Gait analysis of 32 healthy older adults showed that tactile, as compared to smooth, paving increases the variability in timing of foot placement by 20%, thereby indicating a disturbance of the rhythmic gait pattern. Moreover, toe clearance during the swing phase increased by 7% on tactile paving, and the ability to stop upon cue from the traffic light was compromised. These results need to be viewed under the consideration of limitations associated with laboratory studies and real world analysis is needed to fully understand their implications for urban design.

  11. Sustainable Approaches for Stormwater Quality Improvements with Experimental Geothermal Paving Systems

    Directory of Open Access Journals (Sweden)

    Kiran Tota-Maharaj


    Full Text Available This research assesses the next generation of permeable pavement systems (PPS incorporating ground source heat pumps (geothermal paving systems. Twelve experimental pilot-scaled pavement systems were assessed for its stormwater treatability in Edinburgh, UK. The relatively high variability of temperatures during the heating and cooling cycle of a ground source heat pump system embedded into the pavement structure did not allow the ecological risk of pathogenic microbial expansion and survival. Carbon dioxide monitoring indicated relatively high microbial activity on a geotextile layer and within the pavement structure. Anaerobic degradation processes were concentrated around the geotextile zone, where carbon dioxide concentrations reached up to 2000 ppm. The overall water treatment potential was high with up to 99% biochemical oxygen demand removal. The pervious pavement systems reduced the ecological risk of stormwater discharges and provided a low risk of pathogen growth.

  12. Modeling and Simulation of Flow and Formation Damage of Asphalt-Paved Roads

    Directory of Open Access Journals (Sweden)

    M. H. Alawi


    Full Text Available Porous asphalt is a standard asphalt built on aggregate storage bed which allows water to drain through it and reduces stormwater runoff. However, porosity of the porous asphalt and the storage bed may be effectively reduced due to trapping suspended solids from the water or from the asphalt damage. In this paper, we present mathematical modeling and numerical simulation of flow and damage of porous asphalt-paved roads. A mathematical model to describe the fine-particles transport carried by a two-phase flow in a porous medium is presented. The buoyancy, capillarity, and mixed relative permeabilities correlations to fit with the mixed-wet system are considered. Throughout this investigation, we monitor the changing of the fluids properties such as water saturation and solid properties such as porosity and permeability due to trapping the fine-particles.

  13. Malaria Research Priorities in Yemen: Paving the Way for Malaria Elimination

    Directory of Open Access Journals (Sweden)

    Rashad Abdul-Ghani


    Full Text Available Malaria represents a major health problem in Yemen, and it appears that the efforts devoted to its control and elimination only tackle the tip of malaria iceberg. There is an evident gap between research activities and control efforts reflected by the fact that efforts and funding allocation are mainly directed to control activities. Research on basic, clinical and epidemiological aspects of the disease, which could serve elimination efforts, is rather ignored. This can simply be observed by searching online scientific databases, where the majority of published articles are of researchers and post-graduate students. Therefore, organized and collaborative research activities intended to serve the efforts to eliminate the disease are urgently needed, with a fair allocation of funds between research and control activities. The present editorial highlights research priorities needed to pave the way for malaria elimination and the need for bridging the existing gap between research and control strategies

  14. Geochemical modeling and assessment of leaching from carbonated municipal solid waste incinerator (MSWI) fly ash. (United States)

    Wang, Lei; Chen, Qi; Jamro, Imtiaz Ali; Li, Rundong; Li, Yanlong; Li, Shaobai; Luan, Jingde


    Municipal solid waste incinerator (MSWI) fly ashes are characterized by high calcium oxide (CaO) content. Carbon dioxide (CO2) adsorption by MSWI fly ash was discussed based on thermogravimetry (TG)/differential thermal analysis (DTA), minerology analysis, and adapting the Stenoir equation. TG/DTA analysis showed that the weight gain of the fly ash below 440 °C was as high as 5.70 %. An adapted Stenoir equation for MSWI fly ash was discussed. The chloride in MSWI fly ash has a major impact on CO2 adsorption by MSWI fly ash or air pollution control (APC) residues. Geochemical modeling of the critical trace elements copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb), and antimony (Sb) before and after carbonation was performed using a thermodynamic equilibrium model for solubility and a surface complexation model for metal sorption. Leaching of critical trace elements was generally found to be strongly dependent on the degree of carbonation attained, and their solubility appeared to be controlled by several minerals. Adsorption on ferrum (Fe) and aluminum (Al) colloids was also responsible for removal of the trace elements Cd, Pb, and Sb. We used Hakanson's potential ecological risk index (HPERI) to evaluate the risk of trace element leaching in general. The results demonstrate that the ecological risk showed a V-shaped dependency on pH; the optimum pH of the carbonated fly ash was found to be 10.3-11, resulting from the optimum carbonation (liquid-to-solid (L/S) ratio = 0.25, carbonation duration = ∼30-48 h). The dataset and modeling results presented here provide a contribution to assessing the leaching behavior of MSWI fly ash under a wide range of conditions.

  15. Adhesion Strength of Biomass Ash Deposits

    DEFF Research Database (Denmark)

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


    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...

  16. Fly Ash Disposal in Ash Ponds: A Threat to Ground Water Contamination (United States)

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


    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.

  17. Fly Ash Disposal in Ash Ponds: A Threat to Ground Water Contamination (United States)

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


    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.

  18. Acoustic Surveillance of Hazardous Eruptions (ASHE) in Asia (United States)

    Garces, M. A.; Taisne, B.; Blanc, E.; Tupper, A. C.; Ngemaes, M.; Mialle, P.; Murayama, T.


    The ASHE Ecuador (2004-2012) collaboration between Ecuador, Canada, and the US demonstrated the capability to use real-time infrasound to provide low-latency volcanic eruption notifications to the Volcano Ash Advisory Center (VAAC) in Washington DC. The Atmospheric dynamics Research Infrastructure in Europe (ARISE, 2012-2018) supported by the European Commission fosters integrating innovative methods for remote detection and characterization of distant eruptive sources through collaborations with the VAAC Toulouse and the Comprehensive Nuclear-Test-Ban-Treaty Organization (CTBTO). The ASHE Asia project proposes an international collaboration between the Earth Observatory of Singapore, the VAAC Darwin, the Palau National Weather Service, and US and Asian partners, and will receive the support of ARISE, to provide improved early notification of potentially hazardous eruptions in Asia and the Western Pacific using a combination of established technologies and next-generation mobile sensing systems. The increased availability of open seismo-acoustic data in the ASEAN region as well as recent advances in mobile distributed sensors networks will facilitate unprecedented rapid progress in monitoring remote regions for early detection of hazardous volcanic eruptions and other natural disasters.

  19. Volcanic ash fuels anomalous plankton bloom in subarctic northeast Pacific (United States)

    Hamme, Roberta C.; Webley, Peter W.; Crawford, William R.; Whitney, Frank A.; DeGrandpre, Michael D.; Emerson, Steven R.; Eriksen, Charles C.; Giesbrecht, Karina E.; Gower, Jim F. R.; Kavanaugh, Maria T.; Peña, M. Angelica; Sabine, Christopher L.; Batten, Sonia D.; Coogan, Laurence A.; Grundle, Damian S.; Lockwood, Deirdre


    Using multiple lines of evidence, we demonstrate that volcanic ash deposition in August 2008 initiated one of the largest phytoplankton blooms observed in the subarctic North Pacific. Unusually widespread transport from a volcanic eruption in the Aleutian Islands, Alaska deposited ash over much of the subarctic NE Pacific, followed by large increases in satellite chlorophyll. Surface ocean pCO2, pH, and fluorescence reveal that the bloom started a few days after ashfall. Ship-based measurements showed increased dominance by diatoms. This evidence points toward fertilization of this normally iron-limited region by ash, a relatively new mechanism proposed for iron supply to the ocean. The observations do not support other possible mechanisms. Extrapolation of the pCO2 data to the area of the bloom suggests a modest ˜0.01 Pg carbon export from this event, implying that even large-scale iron fertilization at an optimum time of year is not very efficient at sequestering atmospheric CO2.

  20. Airborne volcanic ash; a global threat to aviation (United States)

    Neal, Christina A.; Guffanti, Marianne C.


    The world's busy air traffic corridors pass over or downwind of hundreds of volcanoes capable of hazardous explosive eruptions. The risk to aviation from volcanic activity is significant - in the United States alone, aircraft carry about 300,000 passengers and hundreds of millions of dollars of cargo near active volcanoes each day. Costly disruption of flight operations in Europe and North America in 2010 in the wake of a moderate-size eruption in Iceland clearly demonstrates how eruptions can have global impacts on the aviation industry. Airborne volcanic ash can be a serious hazard to aviation even hundreds of miles from an eruption. Encounters with high-concentration ash clouds can diminish visibility, damage flight control systems, and cause jet engines to fail. Encounters with low-concentration clouds of volcanic ash and aerosols can accelerate wear on engine and aircraft components, resulting in premature replacement. The U.S. Geological Survey (USGS), in cooperation with national and international partners, is playing a leading role in the international effort to reduce the risk posed to aircraft by volcanic eruptions.

  1. Developments in CO2 mineral carbonation of oil shale ash. (United States)

    Uibu, M; Velts, O; Kuusik, R


    Solid waste and atmospheric emissions originating from power production are serious problems worldwide. In the Republic of Estonia, the energy sector is predominantly based on combustion of a low-grade carbonaceous fossil fuel: Estonian oil shale. Depending on the combustion technology, oil shale ash contains 10-25% free lime. To transport the ash to wet open-air deposits, a hydraulic system is used in which 10(7)-10(8) cubic meters of Ca(2+)-ion-saturated alkaline water (pH level 12-13) is recycled between the plant and sedimentation ponds. The goals of the current work were to design an ash-water suspension carbonation process in a continuous mode laboratory-scale plant and to search for potential means of intensifying the water neutralization process. The carbonation process was optimized by cascading reactor columns in which the pH progressed from alkaline to almost neutral. The amount of CO(2) captured from flue gases can reach 1-1.2 million ton at the 2007 production level of the SC Narva Power Plants. Laboratory-scale neutralization experiments were carried out to compare two reactor designs. Sedimentation of PCC particles of rhombohedral crystalline structure was demonstrated and their main characteristics were determined. A new method providing 50x greater specific intensity is also discussed.

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

    Institute of Scientific and Technical Information of China (English)


    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.

  3. 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


    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.

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


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


    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...

  5. Radon emanation fractions from concretes containing fly ash and metakaolin. (United States)

    Taylor-Lange, Sarah C; Juenger, Maria C G; Siegel, Jeffrey A


    Radon ((222)Rn) and progenies emanate from soil and building components and can create an indoor air quality hazard. In this study, nine concrete constituents, including the supplementary cementitious materials (SCMs) fly ash and metakaolin, were used to create eleven different concrete mixtures. We investigated the effect of constituent radium specific activity, radon effective activity and emanation fraction on the concrete emanation fraction and the radon exhalation rate. Given the serious health effects associated with radionuclide exposure, experimental results were coupled with Monte Carlo simulations to demonstrate predictive differences in the indoor radon concentration due to concrete mixture design. The results from this study show that, on average, fly ash constituents possessed radium specific activities ranging from 100 Bq/kg to 200 Bq/kg and emanation fractions ranging from 1.1% to 2.5%. The lowest emitting concrete mixture containing fly ash resulted in a 3.4% reduction in the concrete emanation fraction, owing to the relatively low emanation that exists when fly ash is part of concrete. On average, the metakaolin constituents contained radium specific activities ranging from 67 Bq/kg to 600 Bq/kg and emanation fractions ranging from 8.4% to 15.5%, and changed the total concrete emanation fraction by roughly ±5% relative to control samples. The results from this study suggest that SCMs can reduce indoor radon exposure from concrete, contingent upon SCM radionucleotide content and emanation fraction. Lastly, the experimental results provide SCM-specific concrete emanation fractions for indoor radon exposure modeling.

  6. 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


    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...

  7. Biotic and abiotic factors affect green ash volatile production and emerald ash borer adult feeding preference. (United States)

    Chen, Yigen; Poland, Therese M


    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.

  8. ASH External Web Portal (External Portal) - (United States)

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

  9. AshMeadowsSpeckledDace_CH (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...

  10. AshMeadowsAmargosaPupfish_CH (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. Cementing Properties of Oil Shale Ash

    Institute of Scientific and Technical Information of China (English)


    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.

  12. Volcanic Ash Advisory Database, 1983-2003 (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...

  13. Clay Improvement with Burned Olive Waste Ash

    Directory of Open Access Journals (Sweden)

    Utkan Mutman


    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.


    Institute of Scientific and Technical Information of China (English)

    章新喜; 陈清加


    The effect of removing pyrite and ash from fine coal with electrostatic separator is determined by the electric property of coal, the distribution of corona ion and electrostatic field, and the disperse and even feed. The dielectric constant of coal and mineral matter is studied in this paper and the amendment has been made to survey theory. The oscillogram is adopted to study the distribution of corona ion and electrostatic field. The paper details the study of remoing pyrite and ash from fine coal, and the test results demonstrate the high efficiency of removing pyrite and ash with electrostatic separator.

  15. The ash in forest fire affected soils control the soil losses. Part 1. The pioneer research (United States)

    Cerdà, Artemi; Pereira, Paulo


    After forest fires, the ash and the remaining vegetation cover on the soil surface are the main protection against erosion agents. The control ash exert on runoff generation mechanism was researched during the 90's (Cerdà, 1998a; 1998b). This pioneer research demonstrated that after forest fires there is a short period of time that runoff and surface wash by water is controlled by the high infiltration rates achieved by the soil, which were high due to the effect of ash acting as a mulch. The research of Cerdà (1998a; 1998b) also contributed to demonstrate that runoff was enhanced four month later upon the wash of the ash by the runoff, but also due to the removal of ash due to dissolution and water infiltration. As a consequence of the ephemeral ash cover the runoff and erosion reached the peak after the removal of the ash (usually four month), and for two years the soil erosion reached the peak (Cerdà, 1998a). Research developed during the last decade shown that the ash and the litter cover together contribute to reduce the soil losses after the forest fire (Cerdà and Doerr, 2008). The fate of the ash is related to the climatic conditions of the post-fire season, as intense thunderstorms erode the ash layer and low intensity rainfall contribute to a higher infiltration rate and the recovery of the vegetation. Another, key factor found during the last two decades that determine the fate of the ash and the soil and water losses is the impact of the fauna (Cerdà and Doerr, 2010). During the last decade new techniques were developed to study the impact of ash in the soil system, such as the one to monitor the ash changes by means of high spatial resolution photography (Pérez Cabello et al., 2012), and laboratory approaches that show the impact of ash as a key factor in the soil hydrology throughout the control they exert on the soil water repellency (Bodí et al., 2012). Laboratory approaches also shown that the fire severity is a key factor on the ash chemical

  16. Flue gas desulfurization gypsum and fly ash

    Energy Technology Data Exchange (ETDEWEB)


    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.

  17. Stabilization/solidification of TSCA incinerator ash

    Energy Technology Data Exchange (ETDEWEB)

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


    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.

  18. Wildland fire ash: future research directions (United States)

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


    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

  19. Determination of time- and height-resolved volcanic ash emissions and their use for quantitative ash dispersion modeling: the 2010 Eyjafjallajökull eruption

    Directory of Open Access Journals (Sweden)

    A. Stohl


    Full Text Available The April–May, 2010 volcanic eruptions of Eyjafjallajökull, Iceland caused significant economic and social disruption in Europe whilst state of the art measurements and ash dispersion forecasts were heavily criticized by the aviation industry. Here we demonstrate for the first time that large improvements can be made in quantitative predictions of the fate of volcanic ash emissions, by using an inversion scheme that couples a priori source information and the output of a Lagrangian dispersion model with satellite data to estimate the volcanic ash source strength as a function of altitude and time. From the inversion, we obtain a total fine ash emission of the eruption of 8.3 ± 4.2 Tg for particles in the size range of 2.8–28 μm diameter. We evaluate the results of our model results with a posteriori ash emissions using independent ground-based, airborne and space-borne measurements both in case studies and statistically. Subsequently, we estimate the area over Europe affected by volcanic ash above certain concentration thresholds relevant for the aviation industry. We find that during three episodes in April and May, volcanic ash concentrations at some altitude in the atmosphere exceeded the limits for the "Normal" flying zone in up to 14 % (6–16 %, 2 % (1–3 % and 7 % (4–11 %, respectively, of the European area. For a limit of 2 mg m−3 only two episodes with fractions of 1.5 % (0.2–2.8 % and 0.9 % (0.1–1.6 % occurred, while the current "No-Fly" zone criterion of 4 mg m−3 was rarely exceeded. Our results have important ramifications for determining air space closures and for real-time quantitative estimations of ash concentrations. Furthermore, the general nature of our method yields better constraints on the distribution and fate of volcanic ash in the Earth system.

  20. 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


    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.

  1. Ash transformation during co-firing coal and straw

    DEFF Research Database (Denmark)

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


    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...

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

    Directory of Open Access Journals (Sweden)

    S. Sivakumar


    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.

  3. Comparative study on the characteristics of fly ash and bottom ash geopolymers. (United States)

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


    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.

  4. 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


    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.

  5. Calibration of microbolometer infrared cameras for measuring volcanic ash mass loading (United States)

    Carroll, Russell C.

    greater than 2.0 mg/m3 are considered dangerous to aircraft. This analysis demonstrates that a TIR imaging system for determining whether the volcanic ash density is dangerous for aircraft is feasible for multi-unit Cubesat platforms.

  6. Insight of the fusion behavior of volcanic ash: Implications for Volcanic ash Hazards to Aircraft Safety (United States)

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


    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

  7. 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


    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.

  8. International Database of Volcanic Ash Impacts (United States)

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


    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.

  9. Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

    Directory of Open Access Journals (Sweden)



    Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.

  10. Some Properties of Emulsified Asphalt Paving Mixture at Iraqi Environmental Conditions

    Directory of Open Access Journals (Sweden)

    Shakir.A.Al-Mishhadani* Hasan.H.Al-Baid


    Full Text Available Cold emulsified asphalt mixture is generally a mix made of emulsified asphalt withaggregate. Emulsified asphalt is manufactured from base asphalt, emulsifier agent and waterwith approximate percentage of 40% to 75% asphalt, 0.1% to 2.5% emulsifier and 25% to60% water plus some minor components. This study aims to use the cold emulsified asphaltmixtures for road construction and maintenance in Iraq as an alternative to the hot asphaltmixtures, due to its economical, practical and environmental advantages. This studyfocusedto test and evaluates the emulsified asphalt material properties to be used as paving mixture.The tested properties of emulsified asphalt mixture were bulk density, air voids, dry Marshallstability, wet Marshall stability, retained Marshall stability, flow tests and compared with thecommon used specification.The results indicate that the emulsified asphalt type cationic slowsetting low viscosity (CSS-1 is very suitable with quartz type of aggregate from Al-Nibaayquarry. From many trial mixes it is found that the best percentages of initial residual bitumencontent to produced adequateresults for coating test ,mixing ,compaction ,curing and Marshallstability were ranged from (2.5%, 3%,3.5%,4% and 4.5%, andthe optimum percentage is(3.5%.Finally it can be conducted that the emulsified asphalt mixture is a suitable alternativemixture to the hot asphalt mixture for road construction and maintenance in Iraq.  

  11. Shielded loaded bowtie antenna incorporating the presence of paving structure for improved GPR pipe detection (United States)

    Seyfried, Daniel; Jansen, Ronald; Schoebel, Joerg


    In civil engineering Ground Penetrating Radar becomes more and more a considerable tool for nondestructive testing and exploration of the underground. For example, the detection of existence of utilization pipe networks prior to construction works or detection of damaged spot beneath a paved street is a highly advantageous application. However, different surface conditions as well as ground bounce reflection and antenna cross-talk may seriously affect the detection capability of the entire radar system. Therefore, proper antenna design is an essential part in order to obtain radar data of high quality. In this paper we redesign a given loaded bowtie antenna in order to reduce strong and unwanted signal contributions such as ground bounce reflection and antenna cross-talk. During the optimization process we also review all parameters of our existing antenna in order to maximize energy transfer into ground. The entire process incorporating appropriate simulations along with running measurements on our GPR test site where we buried different types of pipes and cables for testing and developing radar hardware and software algorithms under quasi-real conditions is described in this paper.

  12. From virtue ethics to rights ethics: Did the Reformation pave the way for secular ethics?

    Directory of Open Access Journals (Sweden)

    Nico Vorster


    Full Text Available In chapter four of his book, The unintended Reformation, Brad Gregory argues that ethical thinking since the 1500’s experienced a major shift in emphasis from the teleological concept of a ‘substantive morality of the good’ to liberalism’s ‘formal morality of rights’. He attributes it to the religious upheavals and ‘sociopolitical disruptions’ during the Reformation era. This article probes three elements of Gregory’s argument. Firstly, the article offers a critical assessment of Gregory’s depiction of the Reformation’s stance towards reason. It pays particular attention to the Reformation’s understanding of the effects of sin on the human being’s image of God, reason and the possibility for a shared social ethics. Secondly, this study scrutinises Gregory’s argument that the Reformation created an individualist notion of selfhood in contrast to the Roman Catholic communal notion of selfhood and thereby paved the way for modernism. Lastly, the discussion probes into Gregory’s claim that the Reformation’s ethical paradigm diverged radically from the Latin Christendom paradigm and that this contributed to the subjectivisation of ethics, by replacing a virtue ethics with a rights ethics.

  13. 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.


    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.

  14. 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


    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.

  15. Lipid peroxidation and oxidative status compared in workers at a bottom ash recovery plant and fly ash treatment plants. (United States)

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


    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.

  16. 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.

  17. Interspecific proteomic comparisons reveal ash phloem genes potentially involved in constitutive resistance to the emerald ash borer. (United States)

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


    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.

  18. 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.


    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.

  19. National volcanic ash operations plan for aviation (United States)

    ,; ,


    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

  20. 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


    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.

  1. 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


    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

  2. Ultrasonic and conventional synthesis of NaA zeolite from rice husk ash (United States)

    Farías, T.; de Ménorval, LC; Picazo, O.; Jordán, R.


    In the present work, a simple synthetic route for the production of single phase NaA zeolite is demonstrated. Rice husk ash (RHA) as alternative silica source was employed for the synthesis by conventional hydrothermal and non-conventional ultrasound methods. The zeolite was also synthesized using commercially available silicate for comparison. The effect of the reaction time (2, 4 and 6 h) at a fixed temperature of 70 °C was investigated. The elemental, structural and morphological characterization of the ashes and the synthesized zeolites was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and thermogravimetric analysis (TG/DSC).

  3. Effect of fly ash on the optimum sulfate of Portland Cement (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

  4. Role of fly ash in the removal of organic pollutants from wastewater

    Energy Technology Data Exchange (ETDEWEB)

    M. Ahmaruzzaman [National Institute of Technology, Silchar (India). Department of Chemistry


    Fly ash, a relatively abundant and inexpensive material, is currently being investigated as an adsorbent for the removal of various organic pollutants from wastewater. The wastewater contains various types of phenolic compounds, such as chloro, nitro, amino, and other substituted compounds. Various types of pesticides, such as lindane, malathion, carbofuran, etc., and dyes, such as, methylene blue, crystal violet, malachite green, etc., are also present in the wastewater. These contaminants pollute the water stream. These organic pollutants, such as phenolic compounds, pesticides, and dyes, etc., can be removed very effectively using fly ash as adsorbent. This article presents a detailed review on the role of fly ash in the removal of organic pollutants from wastewater. Adsorption of various pollutants using fly ash has been reviewed. The adsorption mechanism and other influencing factors, favorable conditions, and competitive ions, etc., on the adsorption process have also been discussed in this paper. It is evident from the review that fly ash has demonstrated good removal capabilities for various organic compounds. 171 refs., 3 figs., 5 tabs.

  5. Cytotoxicity and genotoxicity induced by coal and coal fly ash particles samples in V79 cells. (United States)

    León-Mejía, Grethel; Silva, Luis F O; Civeira, Matheus S; Oliveira, Marcos L S; Machado, Miriana; Villela, Izabel Vianna; Hartmann, Andreas; Premoli, Suziane; Corrêa, Dione Silva; Da Silva, Juliana; Henriques, João Antônio Pêgas


    Exposure to coal and coal ashes can cause harmful effects in in vitro and in vivo systems, mainly by the induction of oxidative damage. The aim of this work was to assess cytotoxic and genotoxic effects using the V79 cell line treated with coal and coal fly ash particles derived from a coal power plant located in Santa Catarina, Brazil. Two coal samples (COAL11 and COAL16) and two coal fly ash samples (CFA11 and CFA16) were included in this study. COAL16 was co-firing with a mixture of fuel oil and diesel oil. The comet assay data showed that exposure of V79 cells to coal and coal fly ash particles induced primary DNA lesions. Application of lesion-specific endonucleases (FPG and ENDO III) demonstrated increased DNA effects indicating the presence of high amounts of oxidative DNA lesions. The cytokinesis-block micronucleus cytome assay analysis showed that exposure of V79 cells to high concentrations of coal and coal fly ash particles induced cytotoxic effects (apoptosis and necrosis) and chromosomal instability (nucleoplasmic bridges, nuclear buds, and micronucleus (MN) formation). These results may be associated with compounds contained in the surface of the particles as hazardous elements, ultrafine/nanoparticles, and polycyclic aromatic hydrocarbons (PAHs) which were detected in the samples. Graphical abstract ᅟ.

  6. Degradation of n-butyl xanthate using fly ash as heterogeneous Fenton-like catalyst

    Institute of Scientific and Technical Information of China (English)

    陈绍华; 杜冬云


    Heterogeneous Fenton-like process using fly ash as a catalyst was studied to degrade n-butyl xanthate form aqueous solution. The different reaction parameters on the degradation efficiency of the process were investigated. The fly ash/H2O2 catalyst possesses a high oxidation activity for n-butyl xanthate degradation in aqueous solution. It is found that both the dosage of catalyst and initial solution pH significantly affect the n-butyl xanthate conversion efficient. The results indicate that by using 1.176 mmol/L H2O2 and 1.0 g/L fly ash catalyst with mass fraction of 4.14%Fe(III) oxide at pH 3.0, almost 96.90%n-butyl xanthate conversion and over 96.66%COD removal can be achieved within 120 min with heterogeneous catalysis by fly ash. CS2 as an intermediate of n-butyl xanthate oxidation. Finally, it is demonstrated that the fly ash/H2O2 catalytic oxidation process can be an efficient method for the treatment of n-butyl xanthate containing wastewater.

  7. Studies on synthesis and characteristics of zeolite prepared from Indian fly ash. (United States)

    Prasad, Bably; Maity, Sudip; Sangita, Kumari; Mahato, Arun Kumar; Mortimer, Robert J G


    In the present study, samples of coal fly ash were obtained from seven major Indian thermal power plants. These samples were transformed into fly ash zeolite (FAZ) using hydrothermal activation by treatment with NaOH. All experiments were carried out at 100 degrees C, but with different solid:liquid ratios, different concentrations of alkali and different incubation times. The chemical composition, mineralogy and morphology of the fly ash and FAZ were determined by wet chemical method after Na2CO3 fusion, x-ray diffraction and scanning electron microscopy. The cation exchange capacity of fly ash and FAZ was determined using the ammonium acetate method (IS:2720). The ammonium exchange capacity was determined by the titrimetric method. The experiments demonstrate that zeolite can be synthesized at 100 degrees C using alkali. The cation exchange capacity and ammonium adsorption capacity of FAZ (up to 250 meq/100 g and 22.93 mg NH4+/g respectively) indicate that the FAZ may be potentially useful to reduce heavy metals and other pollutants from contaminated environments. Therefore, zeolitization at low temperature potentially allows waste fly ash to be used in an economically advantageous way.

  8. Effects of ultrasonic treatment on zeolite synthesized from coal fly ash. (United States)

    Belviso, Claudia; Cavalcante, Francesco; Lettino, Antonio; Fiore, Saverio


    The synthesis of zeolites from three samples of fly ash was carried out through a low-temperature (25-60°C) hydrothermal process with a NaOH pre-fusion treatment preceded by sonication. The results were compared with those of conventional hydrothermal syntheses. XRD and SEM investigations demonstrate that the application of ultrasonic treatment facilitates the formation of zeolites at a lower-temperature (25°C) than syntheses not preceded by sonication. No significant difference in type, temperature of crystallization, or amount of zeolites synthesized was noted between the three different samples of fly ash, implying that the chemical composition of fly ash had little influence on the zeolite product within the compositional range of these fly ash precursors. Although there appears to be a correlation between the SiO(2)/Al(2)O(3) ratio of the fly ash and the temperature of zeolite formation by conventional synthesis, no correlation was apparent when ultrasonic pre-treatment was used at low-temperatures.

  9. Routine determination of trace elements in fly ashes by instrumental neutron activation analysis

    Energy Technology Data Exchange (ETDEWEB)

    Szopa, Z.; Dybczynski, R.; Kulisa, K.; Sterlinski, S. [Institute of Nuclear Chemistry and Technology, Warsaw (Poland)


    A method making possible routine determination of 24 trace elements in fly ashes by instrumental neutron activation analysis (INAA) is described. The method employs elemental standards, and the correction for neutron flux gradient in the irradiation package is performed with the aid of Au flux monitors. Important features of the method as: detectability, precision and accuracy are discussed in detail. Reliability of the method was demonstrated by the analysis of several certified reference materials (CRMs). Special attention was devoted to comparison of the experimentally obtained detection limits with those predicted by computer spectra simulation (CSS) method. The elemental enrichment factors calculated for Polish coal fly ash were compared with those typical for Chinese and Canadian fly ashes. (author). 21 refs, 7 figs.

  10. Experimental Investigation on Strength and Water Permeability of Mortar Incorporate with Rice Straw Ash

    Directory of Open Access Journals (Sweden)

    Surajit Munshi


    Full Text Available The utilization of various agricultural residue ash as a pozzolanic material has the potential to reduce both the environmental impact and cost associated with building materials. In this paper, the authors studied the strength and permeability of mortar using different percentages of rice straw ash (RSA as cement replacement and the possibilities of using RSA as a pozzolanic material. Locally available rice straws were burnt at a temperature of 600°C and ground to make RSA. The chemical and physical properties of RSA were studied and the outcome shows that the ash contains about 76% of silica in it. This investigation further focused the strength and water permeability of mortar using RSA, which demonstrates that up to 10% replacement both the strength and permeability have a better result than that of control specimen.

  11. 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)


    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.

  12. Laboratory study of volcanic ash electrification (United States)

    Alois, Stefano; Merrison, Jonathan


    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.

  13. NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)


    The report summarizes unit operating experience and test program progress for 1989 on Colorado-Ute Electric Association's Nucla CFB Demonstration Program. During this period, the objectives of the Nucla Station operating group were to correct problems with refractory durability, resolve primary air fan capacity limitations, complete the high ash and high sulfur coal tests, switch to Salt Creek coal as the operating fuel, and make the unit available for testing without capacity restrictions. Each of these objectives was addressed and accomplished, to varying degrees, except for the completion of the high sulfur coal acceptance tests. (VC)

  14. The Ashkenazic Jewish Bloom syndrome mutation blmAsh is present in non-Jewish Americans of Spanish ancestry. (United States)

    Ellis, N A; Ciocci, S; Proytcheva, M; Lennon, D; Groden, J; German, J


    Bloom syndrome (BS) is more frequent in the Ashkenazic Jewish population than in any other. There the predominant mutation, referred to as "blmAsh," is a 6-bp deletion and 7-bp insertion at nucleotide position 2281 in the BLM cDNA. Using a convenient PCR assay, we have identified blmAsh on 58 of 60 chromosomes transmitted by Ashkenazic parents to persons with BS. In contrast, in 91 unrelated non-Ashkenazic persons with BS whom we examined, blmAsh was identified only in 5, these coming from Spanish-speaking Christian families from the southwestern United States, Mexico, or El Salvador. These data, along with haplotype analyses, show that blmAsh was independently established through a founder effect in Ashkenazic Jews and in immigrants to formerly Spanish colonies. This striking observation underscores the complexity of Jewish history and demonstrates the importance of migration and genetic drift in the formation of human populations.

  15. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    DEFF Research Database (Denmark)

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


    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through...... the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even...... consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted...

  16. 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)


    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.

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

    Chindaprasirt, Prinya; Rattanasak, Ubolluk


    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.

  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). (United States)

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


    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. Changeing of fly ash leachability after grinding (United States)

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


    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.

  20. 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)


    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.

  1. 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)


    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Manz, O.E.


    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.

  3. 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)


    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.

  4. 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)


    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.

  5. Sewage sludge ash — A promising secondary phosphorus source for fertilizer production

    Energy Technology Data Exchange (ETDEWEB)

    Herzel, Hannes, E-mail: [BAM Federal Institute for Materials Research and Testing Richard-Willstätter-Straße 11, 12489 Berlin (Germany); Krüger, Oliver [BAM Federal Institute of Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany); Hermann, Ludwig [Outotec GmbH & Co KG, Ludwig-Erhard-Straße 21, 61440 Oberursel (Germany); Adam, Christian [BAM Federal Institute of Materials Research and Testing, Unter den Eichen 87, 12205 Berlin (Germany)


    Sewage sludge incineration is extensively practiced in some European countries such as the Netherlands, Switzerland, Austria and Germany. A survey of German sewage sludge ash showed that the recovery potential is high, approx. 19,000 t of phosphorus per year. However, the survey also discovered that the bioavailability of phosphorus in the sewage sludge ash is poor and that more than half of the ashes cannot be used as fertilizers due to high heavy metal content. A new thermochemical process for sewage sludge ash treatment was developed that transforms the ash into marketable fertilizer products. Sewage sludge ash was thermochemically treated with sodium and potassium additives under reducing conditions, whereby the phosphate-bearing mineral phases were transformed into plant available phosphates. High P-bioavailability was achieved with a molar Na/P ratio > 1.75 in the starting materials. Sodium sulfate, carbonate and hydroxide performed comparably as additives for this calcination process. Potassium carbonate and -hydroxide have to be added in a molar K/P ratio > 2.5 to achieve comparable P-solubility. The findings of the laboratory scale investigations were confirmed by an industrial demonstration trial for an ash treatment with sodium sulfate. Simultaneously, the volatile transition metal arsenic (61% removal) as well as volatile heavy metals such as cadmium (80%), mercury (68%), lead (39%) and zinc (9%) were removed via the off-gas treatment system. The product of the demonstration trial is characterized by high bioavailability and a toxic trace element mass fraction below the limit values of the German fertilizer ordinance, thus fulfilling the quality parameters for a P-fertilizer. - Highlights: • Direct use of sewage sludge ashes (SSA) as fertilizer often not possible • New approach of SSA treatment aiming at P-fertilizers with high P-bioavailability • Comparison of different Na- and K-bearing additives for the thermochemical process • Evaporation of

  6. 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


    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.

  7. Was the 12.1 ka Icelandic Vedde Ash one of a kind? (United States)

    Lane, C. S.; Blockley, S. P. E.; Mangerud, J.; Smith, V. C.; Lohne, Ø. S.; Tomlinson, E. L.; Matthews, I. P.; Lotter, A. F.


    The Vedde Ash is the most important volcanic event marker layer for the correlation of Late Quaternary palaeoenvironmental archives in Europe and the North Atlantic. First defined from its type site localities near Ålesund, Western Norway, the Vedde Ash has now been traced across much of northern and central Europe, into northwest Russia, within North Atlantic marine sediments and into the Greenland ice cores. The Vedde Ash is thought to derive from an eruption of the Katla volcano in Iceland that occurred midway through the Younger Dryas/Greenland Stadial 1 (GS-1), ˜12.1 ka BP. Visible and cryptotephra deposits of the Vedde Ash have been found in numerous stratified sites with robust chronologies, which allow its age to be constrained and its dispersal to be mapped. The eruption must have been highly explosive, however few proximal outcrops have been confirmed and this crucial ash layer remains almost exclusively distally-described and characterised using major element glass compositions. The widespread distribution, stratigraphic associations and consistent major element glass chemistry have led the Quaternary tephrochronological community to see the Vedde Ash as a robust and unique chronological marker layer for the Last Glacial to Interglacial Transition (˜10-18 ka BP). Here we present new glass analyses of the Vedde Ash from multiple sites around the dispersal area, using a full suite of compositional analysis, including for the first time, single-grain trace element data. These data demonstrate the strong compositional coherence of Vedde Ash deposits. However, comparison with major, minor, and trace element compositional data from several other distally-described Icelandic tephras reveals that both before and after the Younger Dryas chronozone, there were eruptions that generated widespread tephra layers that have comparable glass shard compositions to the Vedde Ash. This implies that these numerous events not only hail from the same volcanic system, but

  8. Characterization of fly ash from bio and municipal waste

    DEFF Research Database (Denmark)

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


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

  9. Ash Deposition Trials at Three Power Stations in Denmark

    DEFF Research Database (Denmark)

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


    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...

  10. The Rheology of Vegetative Ash-laden Debris Flows (United States)

    Burns, K. A.; Gabet, E.


    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.

  11. 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))


    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.

  12. Observation of Eyjafjallajökull volcano ash over Poland (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.


    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.

  13. Economic analysis of emerald ash borer (Coleoptera: Buprestidae) management options. (United States)

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


    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.

  14. 77 FR 55895 - Permanent Closure of Cincinnati Blue Ash Airport (United States)


    ... 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...

  15. Evaluation of Pollutant Leaching Potential of Coal Ashes for Recycling (United States)

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


    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.

  16. 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


    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

  17. [Effects of Chinese prickly ash orchard on soil organic carbon mineralization and labile organic carbon in karst rocky desertification region of Guizhou province]. (United States)

    Zhang, Wen-Juan; Liao, Hong-Kai; Long, Jian; Li, Juan; Liu, Ling-Fei


    Taking 5-year-old Chinese prickly ash orchard (PO-5), 17-year-old Chinese prickly ash orchard (PO- 17), 30-year-old Chinese prickly ash orchard (PO-30) and the forest land (FL, about 60 years) in typical demonstration area of desertification control test in southwestern Guizhou as our research objects, the aim of this study using a batch incubation experiment was to research the mineralization characteristics of soil organic carbon and changes of the labile soil organic carbon contents at different depths (0-15 cm, 15-30 cm, and 30-50 cm). The results showed that: the cumulative mineralization amounts of soil organic carbon were in the order of 30-year-old Chinese prickly ash orchard, the forest land, 5-year-old Chinese prickly ash orchard and 17-year-old Chinese prickly ash orchard at corresponding depth. Distribution ratios of CO2-C cumulative mineralization amount to SOC contents were higher in Chinese prickly ash orchards than in forest land at each depth. Cultivation of Chinese prickly ash in long-term enhanced the mineralization of soil organic carbon, and decreased the stability of soil organic carbon. Readily oxidized carbon and particulate organic carbon in forest land soils were significantly more than those in Chinese prickly ash orchards at each depth (P carbon and particulate organic carbon first increased and then declined at 0-15 cm and 15-30 cm depth, respectively, but an opposite trend was found at 30-50 cm depth. At 0-15 cm and 15-30 cm, cultivation of Chinese prickly ash could be good for improving the contents of labile soil organic carbon in short term, but it was not conducive in long-term. In this study, we found that cultivation of Chinese prickly ash was beneficial for the accumulation of labile organic carbon at the 30-50 cm depth.


    Energy Technology Data Exchange (ETDEWEB)

    Jan D. Miller; Terrence Chatwin; Jan Hupka; Doug Halbe; Tao Jiang; Bartosz Dabrowski; Lukasz Hupka


    The two-year Department of Energy (DOE) project ''Treatment of Cyanide Solutions and Slurries Using Air-Sparged Hydrocyclone (ASH) Technology'' (ASH/CN) has been completed. This project was also sponsored by industrial partners, ZPM Inc., Elbow Creek Engineering, Solvay Minerals, EIMCO-Baker Process, Newmont Mining Corporation, Cherokee Chemical Co., Placer Dome Inc., Earthworks Technology, Dawson Laboratories and Kennecott Minerals. Development of a new technology using the air-sparged hydrocyclone (ASH) as a reactor for either cyanide recovery or destruction was the research objective. It was expected that the ASH could potentially replace the conventional stripping tower presently used for HCN stripping and absorption with reduced power costs. The project was carried out in two phases. The first phase included calculation of basic processing parameters for ASH technology, development of the flowsheet, and design/adaptation of the ASH mobile system for hydrogen cyanide (HCN) recovery from cyanide solutions. This was necessary because the ASH was previously used for volatile organics removal from contaminated water. The design and modification of the ASH were performed with the help from ZPM Inc. personnel. Among the modifications, the system was adapted for operation under negative pressure to assure safe operating conditions. The research staff was trained in the safe use of cyanide and in hazardous material regulations. Cyanide chemistry was reviewed resulting in identification of proper chemical dosages for cyanide destruction, after completion of each pilot plant run. The second phase of the research consisted of three field tests that were performed at the Newmont Mining Corporation gold cyanidation plant near Midas, Nevada. The first field test was run between July 26 and August 2, 2002, and the objective was to demonstrate continuous operation of the modified ASH mobile system. ASH units were applied for both stripping and absorption

  19. Classification of volcanic ash particles from Sakurajima volcano using CCD camera image and cluster analysis (United States)

    Miwa, T.; Shimano, T.; Nishimura, T.


    total luminance=(R+G+B)/665. We classify the volcanic ash particles from the Dendrograms into three groups based on the euclid distance. The groups are named as Group A, B and C in order of increasing of the average value of total luminance. The classification shows that the numbers of particles belonging to Group A, B and C are 77, 25 and 6 in Feb, 09, 2009 sample, and 102, 19 and 6 in Jan, 13, 2010 sample, respectively. The examination under stereoscopic microscope suggests that Group A, B and C mainly correspond with juvenile, altered and free-crystal particles, respectively. So the result of classification by present method demonstrates a difference in the contribution of juvenile material between the two days. To evaluate reliability of our classification, we classify pseudo-samples in which errors of 10% are added in the measured parameters. We apply our method to one thousand psuedo-samples, and the result shows that the numbers of particles classified into the three groups vary less than 20 % of the total number of 235 particles. Our system can classify 120 particles within 6 minutes so that we easily increase the number of ash particles, which enable us to improve reliabilities and resolutions of the classification and to speedily capture temporal changes of the property of ash particles from active volcanoes.

  20. 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:; Moreno Gutiérrez, M. [Universidad Pedagógica y Tecnológica de Colombia, UPTC, Grupo de Física Nuclear Aplicada y Simulación (Colombia)


    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.

  1. 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


    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.

  2. Mineral processing and characterization of coal waste to be used as fine aggregates for concrete paving blocks

    Directory of Open Access Journals (Sweden)

    C. R. Santos

    Full Text Available Commercial coal production in the southern region of Brazil has been occurring since the beginning of the twentieth century. Due to the geological characteristics of the region, large amounts of solid wastes are generated. The aim of this work was to evaluate the use of coal waste to produce concrete paving blocks. A procedure to process the coal waste with the purpose of reducing the sulfur content and changing the particle size distribution of the material to meet the specification of fine aggregates was developed. The methodology considered the following steps: (a sampling of a coal mining waste; (b gravity separation of the fraction with specific gravity between 2.4 and 2.8; (c comminution of the material and particle size analysis; (d technological characterization of the material and production of concrete paving blocks; and (e acidity generation prediction (environmental feasibility. The results showed that the coal waste considered in this work can be used to replace conventional sand as a fine aggregate for concrete paving blocks in a proportion of up to 50%. This practice can result in cleaner coal production and reduce the demand for exploitation of sand deposits.

  3. Lixiviation of fly ash. Uitloging van vliegas

    Energy Technology Data Exchange (ETDEWEB)

    Verhagen, L.


    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.

  4. Climate change and the ash dieback crisis (United States)

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


    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

  5. Heavy metals in MSW incineration fly ashes

    DEFF Research Database (Denmark)

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


    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...

  6. Phosphorus recovery from sewage sludge char ash

    NARCIS (Netherlands)

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


    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

  7. 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


    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.

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


    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.

  9. Distinguishing defensive characteristics in the phloem of ash species resistant and susceptible to emerald ash borer. (United States)

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


    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.

  10. Emerald ash borer and the urban forest: Changes in landslide potential due to canopy loss scenarios in the City of Pittsburgh, PA. (United States)

    Pfeil-McCullough, Erin; Bain, Daniel J; Bergman, Jeffery; Crumrine, Danielle


    Emerald ash borer is expected to kill thousands of ash trees in the eastern U.S. This research develops tools to predict the effect of ash tree loss from the urban canopy on landslide susceptibility in Pittsburgh, PA. A spatial model was built using the SINMAP (Stability INdex MAPping) model coupled with spatially explicit scenarios of tree loss (0%, 25%, 50%, and 75% loss of ash trees from the canopy). Ash spatial distributions were estimated via Monte Carlo methods and available vegetation plot data. Ash trees are most prevalent on steeper slopes, likely due to urban development patterns. Therefore, ash loss disproportionately increases hillslope instability. A 75% loss of ash resulted in roughly 800 new potential landslide initiation locations. Sensitivity testing reveals that variations in rainfall rates, and friction angles produce minor changes to model results relative to the magnitude of parameter variation, but reveal high model sensitivity to soil density and root cohesion values. The model predictions demonstrate the importance of large canopy species to urban hillslope stability, particularly on steep slopes and in areas where soils tend to retain water. To improve instability predictions, better characterization of urban soils, particularly spatial patterns of compaction and species specific root cohesion is necessary. The modeling framework developed in this research will enhance assessment of changes in landslide risk due to tree mortality, improving our ability to design economically and ecologically sustainable urban systems.

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  12. Future fly ash marketing; Flugaschevermarktung in der Zukunft

    Energy Technology Data Exchange (ETDEWEB)

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


    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.)

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

    Lifescience Database Archive (English)

    Full Text Available Ash2l Blood + mm9 ...

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

    Lifescience Database Archive (English)

    Full Text Available ash1 Cell line + dm3 ...

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

    Lifescience Database Archive (English)

    Full Text Available ash2 Larvae + dm3 ... ...

  16. Pb-free Radiation Shielding Glass Using Coal Fly Ash

    Directory of Open Access Journals (Sweden)

    Watcharin Rachniyom


    Full Text Available In this work, Pb-free shielding glass samples were prepared by the melt quenching technique using subbituminous fly ash (SFA composed of xBi2O3 : (60-xB2O3 : 10Na2O : 30SFA (where x = 10, 15, 20, 25, 30 and 35 by wt%. The samples were investigated for their physical and radiation shielding properties. The density and hardness were measured. The results showed that the density increased with the increase of Bi2O3 content. The highest value of hardness was observed for glass sample with 30 wt% of Bi2O3 concentration. The samples were investigated under 662 keV gamma ray and the results were compared with theoretical calculations. The values of the mass attenuation coefficient (μm, the atomic cross section (σe and the effective atomic number (Zeff were found to increase with an increase of the Bi2O3 concentration and were in good agreement with the theoretical calculations. The best results for the half-value layer (HVL were observed in the sample with 35 wt% of Bi2O3 concentration, better than the values of barite concrete. These results demonstrate the viability of using coal fly ash waste for radiation shielding glass without PbO in the glass matrices.

  17. Effective utilization of waste ash from MSW and coal co-combustion power plant: Zeolite synthesis. (United States)

    Fan, Yun; Zhang, Fu-Shen; Zhu, Jianxin; Liu, Zhengang


    The solid by-product from power plant fueled with municipal solid waste and coal was used as a raw material to synthesize zeolite by fusion-hydrothermal process in order to effectively use this type of waste material. The effects of treatment conditions, including NaOH/ash ratio, operating temperature and hydrothermal reaction time, were investigated, and the product was applied to simulated wastewater treatment. The optimal conditions for zeolite X synthesis were: NaOH/ash ratio=1.2:1, fusion temperature=550 degrees C, crystallization time=6-10 h and crystallization temperature=90 degrees C. In the synthesis process, it was found that zeolite X tended to transform into zeolite HS when NaOH/ash ratio was 1.8 or higher, crystallization time was 14-18 h, operating temperature was 130 degrees C or higher. The CEC value, BET surface area and pore volume for the synthesized product at optimal conditions were 250 cmol kg(-1), 249 m(2) g(-1) and 0.46 cm(3) g(-1) respectively, higher than coal fly ash based zeolite. Furthermore, when applied to Zn(2+) contaminated wastewater treatment, the synthesized product presented larger adsorption capacity and bond energy than coal fly ash based zeolite, and the adsorption isotherm data could be well described by Langmuir and Freundlich isotherm models. These results demonstrated that the special type of co-combustion ash from power plant is suitable for synthesizing high quality zeolite, and the products are suitable for heavy metal removal from wastewater.

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

    DEFF Research Database (Denmark)

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


    Due to relatively high concentrations of Cd, biomass combustion fly ashes often fail to meet Danish legislative requirements for recycling as fertilizer. In this study, the potential of using electrodialytic remediation for removal of Cd from four different biomass combustion fly ashes was invest......Due to relatively high concentrations of Cd, biomass combustion fly ashes often fail to meet Danish legislative requirements for recycling as fertilizer. In this study, the potential of using electrodialytic remediation for removal of Cd from four different biomass combustion fly ashes...... the final Cd concentration was below 2.0. mg Cd/kg DM in at least one experiment done with each ash. This was obtained within 2 weeks of remediation and at liquid to solid (L/S) ratios of L/S 16 for the pre-washed straw ash and L/S 8 for the straw, co-firing and wood ash. © 2013 Elsevier B.V....

  19. Fly ash of mineral coal as ceramic tiles raw material. (United States)

    Zimmer, A; Bergmann, C P


    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.

  20. Experimental study on fly ash capture mercury in flue gas

    Institute of Scientific and Technical Information of China (English)



    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.

  1. Residual Ash Formation during Suspension-Firing of Biomass

    DEFF Research Database (Denmark)

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


    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...

  2. Volcanic Ash fall Impact on Vegetation, Colima 2005 (United States)

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


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

  3. Spatial trends in S and Cl in ash leachates of the May 18th, 1980 eruption of Mt. St Helens (United States)

    Ayris, Paul M.; Delmelle, Pierre; Durant, Adam J.; Damby, David E.; Maters, Elena C.


    It has long been known that surficial deposits of salts and acids on volcanic ash particles derive from interactions of ash with sulphur and halide species within the eruption plume and volcanic cloud. These compounds are mobilised as ash particles are wetted, and beneficial or detrimental environmental and health impacts may be induced where the most concentrated solutions are produced. However, limited mechanistic understanding of gas-ash interactions currently precludes prediction of the spatial distribution or variation in leachate chemistry and concentration following an eruption. Sampling and leachate analysis of freshly-fallen ash therefore offers the sole method by which such variations can be observed. Previous ash leachate studies often involve a limited number of ash samples, and utilise a 'one-dimensional' analysis that considers variation in terms of absolute distance from the source volcano. Here, we demonstrate that extensive sampling and a 'two-dimensional' analysis can uncover more complex spatial trends. We compiled over 358 leachate compositions from the May 18th 1980 eruption of Mt. St. Helens. Of the water-extracted leachates, only 95 compositions from ash sampled at 45 localities between 35 and 1129 km from the volcano are sufficiently documented to be retrospectively comparable. To consider the effects of intra-deposit variability, we calculated average concentrations of leachate data within 11×22 km grid cells across the region, and defined a data quality parameter to reflect confidence in the derived values. To investigate any dependence of leachate composition on the grain size distribution, we generated an interpolated map of geometric specific surface area variation across the deposit, normalising ash leachate data to the calculated specific surface area at the corresponding sampling location. The data treatment identifies S and Cl enrichments in proximal blast deposits; relatively constant Cl concentrations across the ashfall deposits

  4. Suggestion for a course of action on recycling wood ash to forests; Foerslag till handlingsplan foer askaaterfoering

    Energy Technology Data Exchange (ETDEWEB)

    Bjurstroem, Henrik [AaF-Energi and Miljoe AB, Stockholm (Sweden)


    The purpose of the study reported here is a suggestion for a course of action that could be adopted by The Swedish Thermal Research Institute, within its program 'Environmentally correct utilization of ashes', with regard to recycling wood ashes to forest soils. Past and present activities concerning recycling to forests, incl. R and D, have been reviewed as a first step towards this goal. Thereafter, the present situation is discussed and some important actions are proposed. The assumption underlying the study is that wood ash shall be recycled, i.e. spread on forest soils, in order to compensate for the removal of mineral nutrients when whole trees are harvested. Account is taken neither of the discussion whether recycling ashes is necessary nor of alternative uses which might be more economically interesting. Actions that the producers of ashes might consider are the following: to establish a structured procedure to identify obstacles and actions to remove these. The question why ashes are recycled or not is complex, and it may be difficult to reduce it to a single question and answer. Actions that may be considered could be more information, improved organizational procedures, etc. depending on the obstacle: to try to build up more interest for recycling ashes by identifying areas where also a short term benefit for growth can be demonstrated and promoting the spreading of ashes there. It should be noted, though, reservations stated by the National Board of Forestry and the Swedish Energy Agency: spreading ash to peat soil is not recycling and spreading to nitrogen-burdened soil is not desirable; to develop methods for quality assurance, which would lead to consistent and better-known properties for the wood ashes. This includes standardization; to take part in the work aiming at the requirements on leaching properties that probably will be included in revised guidelines from 2005, or to perform parallel work in order to build up necessary know-how or

  5. Effects of nano-SiO(2) and different ash particle sizes on sludge ash-cement mortar. (United States)

    Lin, K L; Chang, W C; Lin, D F; Luo, H L; Tsai, M C


    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. Generation of volcanic ash: a textural study of ash produced in various laboratory experiments (United States)

    Lavallée, Yan; Kueppers, Ulrich; Dingwell, Donald B.


    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

  7. Production of ceramics from coal fly ash

    Directory of Open Access Journals (Sweden)

    Angjusheva Biljana


    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.

  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


    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)


    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. 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)


    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)

  11. Sustainable use of biofuel by recycling ash to forests: treatment of biofuel ash. (United States)

    Mahmoudkhani, Maryam; Richards, Tobias; Theliander, Hans


    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. Simualting the Phase Separated rp-ash (United States)

    Caplan, Matthew; Horowitz, Chuck; Berry, Donald


    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.

  13. Control and follow-up of fly ash roads - Communication and Acceptance; Kontroll och uppfoeljning av askvaegar - Kommunikation och acceptans

    Energy Technology Data Exchange (ETDEWEB)

    Macsik, Josef; Edeskaer, Tommy; Hellman, Fredrik


    The report is aimed at those who perform or plan to perform stabilization of the unbound layers or terrace gravel roads or industrial areas, with binder where a major binder component is fly ash from bio-peat or coal fuel. Stabilization of unbound layers of road structures is a promising technique from technical, economical and environmental point of view. The need of demonstration projects on road sections to show the relationship of laboratory measurements and field measurements are great in order to promote this stabilization technique. Results from follow-up of several stabilized distances and industrial surfaces are presented, where the fly ash is a binder component. The results complement the guidance, Munde et al. (2006) respect to durability, environmental characteristics on several years of perspective. Our hope is that report will serve as a support for the implementation of demonstration projects of stabilized terrace or unbound layers of fly ash as binder component.

  14. On a Steel Horse I Ride: A History of the MH-53 Pave Low Helicopters in War and Peace (United States)


    guys sang it, they sang it loud and enthusiastically. It’s a Pave Low thing. Notes 1. “Air Force Special Operations Command,” USAF fact sheet . 2...then switched to flying H-3s—known as “ Banana Boats”—at Patrick AFB, Florida, where his unit provided launch support for the Apollo space program...Staff Summary Sheet , Doctrinal Employment Concept of MH-53 and HC-130 Aircraft, 7 Dec 1987, and supporting docs., file: SOJ3 MC-130/MH 53 Basing Pro

  15. Inorganic contaminants attenuation in acid mine drainage by fly ash and fly ash-ordinary Portland cement (OPC) blends : column experiments

    Energy Technology Data Exchange (ETDEWEB)

    Gitari, W.M. [Venda Univ., Thohoyandou (South Africa). Dept. of Ecology and Resources Management, School of Environmental Studies; Petrik, L.F.; Etchebers, O. [Western Cape Univ., Bellville (South Africa). Environmental and Nanosciences Group, Dept. of Chemistry; Key, D.L. [Western Cape Univ., Bellville (South Africa). Dept. of Chemistry; Okujeni, C. [Western Cape Univ., Bellville (South Africa). Dept. of Earth Sciences


    The infiltration of acid mine drainage (AMD) material into mine voids is one of the environmental impacts of underground coal mining. In this study, the mitigation of AMD in a mine void was simulated in laboratory conditions. Various mixtures of fly ash, solid residues, and Portland cement were added to packed columns over a 6-month period. The fly ash additions generated near-neutral to alkaline pH levels, which in turn induced precipitation, co-precipitation, and adsorption contaminant attenuation mechanisms. A modelling study demonstrated that the precipitation of ferrihydrite, Al-hydroxides, Al-oxyhydroxysulphates, gypsum, ettringite, manganite, and rhodochrosite lowered contaminant levels. Results of the study indicated that the pH regime and acidity level of the AMD strongly influenced both the leaching of the toxic trace elements as well as the attenuation of the AMD. 3 refs., 2 figs.

  16. Coal Fly Ash Ceramics: Preparation, Characterization, and Use in the Hydrolysis of Sucrose

    Directory of Open Access Journals (Sweden)

    Ricardo Pires dos Santos


    Full Text Available Coal ash is a byproduct of mineral coal combustion in thermal power plants. This residue is responsible for many environmental problems because it pollutes soil, water, and air. Thus, it is important to find ways to reuse it. In this study, coal fly ash, obtained from the Presidente Médici Thermal Power Plant, was utilized in the preparation of ceramic supports for the immobilization of the enzyme invertase and subsequent hydrolysis of sucrose. Coal fly ash supports were prepared at several compaction pressures (63.66–318.30 MPa and sintered at 1200°C for 4 h. Mineralogical composition (by X-ray diffraction and surface area were studied. The ceramic prepared with 318.30 MPa presented the highest surface area (35 m2/g and amount of immobilized enzyme per g of support (76.6 mg/g. In assays involving sucrose inversion, it showed a high degree of hydrolysis (around 81% even after nine reuses and 30 days’ storage. Therefore, coal fly ash ceramics were demonstrated to be a promising biotechnological alternative as an immobilization support for the hydrolysis of sucrose.

  17. Arsenic and copper stabilisation in a contaminated soil by coal fly ash and green waste compost. (United States)

    Tsang, Daniel C W; Yip, Alex C K; Olds, William E; Weber, Paul A


    In situ metal stabilisation by amendments has been demonstrated as an appealing low-cost remediation strategy for contaminated soil. This study investigated the short-term leaching behaviour and long-term stability of As and Cu in soil amended with coal fly ash and/or green waste compost. Locally abundant inorganic (limestone and bentonite) and carbonaceous (lignite) resources were also studied for comparison. Column leaching experiments revealed that coal fly ash outperformed limestone and bentonite amendments for As stabilisation. It also maintained the As stability under continuous leaching of acidic solution, which was potentially attributed to high-affinity adsorption, co-precipitation, and pozzolanic reaction of coal fly ash. However, Cu leaching in the column experiments could not be mitigated by any of these inorganic amendments, suggesting the need for co-addition of carbonaceous materials that provides strong chelation with oxygen-containing functional groups for Cu stabilisation. Green waste compost suppressed the Cu leaching more effectively than lignite due to the difference in chemical composition and dissolved organic matter. After 9-month soil incubation, coal fly ash was able to minimise the concentrations of As and Cu in the soil solution without the addition of carbonaceous materials. Nevertheless, leachability tests suggested that the provision of green waste compost and lignite augmented the simultaneous reduction of As and Cu leachability in a fairly aggressive leaching environment. These results highlight the importance of assessing stability and remobilisation of sequestered metals under varying environmental conditions for ensuring a plausible and enduring soil stabilisation.

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

    Directory of Open Access Journals (Sweden)

    Pinar Terzioglu


    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.

  19. Ash salts and bodily affects: Witoto environmental knowledge as sexual education (United States)

    Alvaro Echeverri, Juan; Enokakuiodo Román-Jitdutjaaño, Oscar


    This letter addresses the indigenous discourse on a set of plant species used by the Witoto Indians of Northwest Amazonia to extract ash or vegetable salt, obtained from the combustion of the tissues of vegetable species, filtering of the ashes, and desiccation of the resulting brine. It aims to demonstrate how the study of the human condition is carried out through a reading of natural entities. The method employed is the indexical analysis of a discourse uttered by the elder Enokakuiodo in the Witoto language from 1995 to 1998, in a verbal genre called rafue, one of several genres of the ‘language of the yard of coca’. The species used to extract ash salt are conceived of as coming from the body of the Creator and as an image of the human body. The rafue of salt performs, in words and gestures, a narrative of human affects and capacities by reading ecological, biological, cultural and linguistic indices from a set of plant species. This discourse on plant species is a discourse on the control and management of bodily affects and capacities, represented as ash salts, that are lessons about sexual development which the Creator left for humanity as a guide—a ‘sexual education’.

  20. Performance Evaluation of Steel Fibres in Rice Husk Ash Substituted Concretes

    Directory of Open Access Journals (Sweden)

    A. Sivakumar


    Full Text Available The potential use of supplementary cementitious materials in plain cement concrete for improving concrete properties has been a growing concern in recent years. In addition, the effective strengthening of the matrix by fibre reinforcements to avoid brittle failure is another requirement for plain concrete. This provided the motivation for exploring the benefits of rice husk ash (RHA as a cement replacement material and the addition of steel fibres for reducing brittleness in concrete. The rice husk ash used in this study was the residue of burnt raw rice husk sintered in a muffle furnace at 800 °C. The fine particle size of the rice husk ash provided an early pozzolanic reaction upon cement hydration and thus resulted in high cementing efficiency. This paper reports a systematic evaluation of the mechanical properties of rice husk ash substituted concrete mixtures containing RHA as a partial cement substitute at replacement levels of 10% and 20% by weight of cement, with different dosages of steel fibres. Our experimental results demonstrated that 10% RHA substitution led to improved compressive properties compared to plain concrete. The highest increase of split tensile and flexural strength was reported in the case of RHA substituted concrete with steel fibre added.

  1. Mechanical Properties and Morphological Study of Fly-Ash-Bagasse Composites (United States)

    Verma, Deepak; Gope, Prakash Chandra; Maheshwari, Mohit Kumar; Sharma, Ravinder Kumar


    In recent years the natural fiber epoxy composite has attracted substantial importance as a potential structural material. The natural fiber composites can be very cost effective material. In the present investigation the development of a Fly ash—Bagasse fiber composite material has been discussed. The Bagasse fiber has been used in two different sizes for the developed material. In two developed composites, diameter of Bagasse fiber has been varied between 13-16 μm and 83-95 μm in length. Correspondingly in other two developed composites; length of Bagasse fiber has been varied from 1 to 5 mm. It was observed that the density decreases by mixing the fiber was more as compared to the composite having both Bagasse fiber and Fly ash. A Bagasse fiber composite with size in the range of μm exhibited better tensile strength than the composite having Bagasse fiber size in mm. The compressive strength of the material increases, if Fly ash alone is used for the composite material but, when Bagasse fiber was mixed with the Fly ash, it was found that there has been a decrease in the compressive strength. It was also observed that there has been a decrease in the flexural strength of the material by mixing the Bagasse fiber in the matrix. The microstructure of composite material was investigated by using Scanning Electron Microscope. The images from Scanning Electron Microscope demonstrated that the Fly ash and Bagasse fiber particles are uniformly distributed over the matrix.

  2. Stabilisation of acid generating waste rock with fly ash : immobilization of arsenic under alkaline conditions

    Energy Technology Data Exchange (ETDEWEB)

    Backstrom, M. [Orebro Univ. (Sweden). Man-Technology Environment Research Centre; Sartz, L. [Bergslagen, Kopparberg (Sweden)


    This study evaluated the potential for using fly ash as an alkaline material for increasing the pH and decreasing arsenic leaching from highly acidic mine waste. A wood ash sample known to contain high concentrations of both calcium and barium was tested with highly acidic mine waste samples that leached approximately 200 mg/L of arsenic at a liquid/solid ratio of 2. Samples were mixed with the fly ash. Control samples consisted of only mine waste, while the amended samples contained 10 g of mine waste and 10 g of wood ash. Ultra pure water was used as a leachant for both systems until the liquid-solid ratio that corresponded to 900 years of drainage for a waste pile that was 3 m high with an annual run-off of 300 mm. Results of the experimental study showed that the pH in the control increased from 1.7 to 2.7, while the pH in the amended system decreased from 12.6 to 11.5. Initial concentrations of arsenic decreased by almost 3 orders of magnitude in the amended systems. Co-precipitation with the iron, and the calcium arsenate precipitation process were identified as the principal arsenic immobilization mechanisms. The study demonstrated that under the right chemical conditions, alkaline amendments can be used to reduce arsenic leaching from mine wastes. 5 refs., 2 tabs., 1 fig.

  3. Catalytic oxidation of gaseous reduced sulfur compounds using coal fly ash. (United States)

    Kastner, James R; Das, K C; Melear, Nathan D


    Activated carbon has been shown to oxidize reduced sulfur compounds, but in many cases it is too costly for large-scale environmental remediation applications. Alternatively, we theorized that coal fly ash, given its high metal content and the presence of carbon could act as an inexpensive catalytic oxidizer of reduced sulfur compounds for "odor" removal. Initial results indicate that coal fly ash can catalyze the oxidization of H(2)S and ethanethiol, but not dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) at room temperature. In batch reactor systems, initial concentrations of 100-500 ppmv H(2)S or ethanethiol were reduced to 0-2 ppmv within 1-2 and 6-8 min, respectively. This was contrary to control systems without ash in which concentrations remained constant. Diethyl disulfide was formed from ethanethiol substantiating the claim that catalytic oxidation occurred. The presence of water increased the rate of adsorption/reaction of both H(2)S and ethanethiol for the room temperature reactions (23-25 degrees C). Additionally, in a continuous flow packed bed reactor, a gaseous stream containing an inlet H(2)S concentration of 400-500 ppmv was reduced to 200 ppmv at a 4.6s residence time. The removal efficiency remained at 50% for approximately 4.6h or 3500 reactor volumes. These results demonstrate the potential of using coal fly ash in reactors for removal of H(2)S and other reduced sulfur compounds.

  4. Effect of Fly Ash and Carbon Reinforcement on Dry Sliding Wear Behaviour of Red Mud

    Directory of Open Access Journals (Sweden)

    Harekrushna Sutar


    Full Text Available This paper explains the sliding wear performance of red mud, fly ash, and carbon composite coating on mild steel. The complex mixture of red mud, fly ash, and carbon is plasma sprayed at 9 kW operating power level. The coatings are examined to study the coating morphology, XRD phase transformation, wear rate, and wear morphology. Wear rate (in terms of cumulative mass loss with sliding time has been demonstrated in the study. At first pure red mud is plasma coated to observe the coating characteristics and then compounded with 20% carbon, 30% carbon, and 20% carbon + 30% fly ash, separately by weight and sliding wear test conducted using pin on disc wear tester. The trial was performed at fixed track diameter of 100 mm and at sliding speed of 100 rpm (0.523 m/s at a load of 30 N. The results are compared. Declined cumulative mass loss by inclusion of fly ash and carbon is seen. This might be due to augmented interfacial tension and dense film build-up at boundary layer.

  5. Occupational exposure and DNA strand breakage of workers in bottom ash recovery and fly ash treatment plants. (United States)

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


    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.

  6. Crowdsourcing genomic analyses of ash and ash dieback – power to the people

    Directory of Open Access Journals (Sweden)

    MacLean Dan


    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 and a public GitHub repository.

  7. The use of coal mining wastes for manufacturing paving materials; Los esteriles del carbon como materia prima para la fabricacion de materiales para pavimentacion

    Energy Technology Data Exchange (ETDEWEB)


    This project was aimed at proving the technical feasibility of the use of coal mining wastes in the manufacturing of paving materials; floor-tiles, flags, paving-stones, grit stones, etc.. With that aim, four types of coal mining wastes were selected out of an inventory and several tests were conducted and following the results, the most appropriate coal mining wastes, the acceptance limits and the quality control tests to be applied to the materials obtained from coal mining wastes as starting materials for the manufacturing of paving materials were established. Different laboratory test were conducted on the manufacturing of flags, floor-tiles and paving-stones. In addition, semi-industrial scale tests were carried out on the manufacturing of grit stones. Preliminary manufactory designs were elaborated for both material types. The study proved that coal mining wastes in a mixture with other raw materials can be used in the manufacturing of paving materials: floor-tiles, flags, paving-stones, grit stones. (Author)

  8. Environmental impact of using fly ash in concrete

    Energy Technology Data Exchange (ETDEWEB)


    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.

  9. Volcanic ash as an oceanic iron source and sink (United States)

    Rogan, Nicholas; Achterberg, Eric P.; Le Moigne, Frédéric A. C.; Marsay, Chris M.; Tagliabue, Alessandro; Williams, Richard G.


    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.

  10. Biofuel Combustion Fly Ash Influence on the Properties of Concrete

    Directory of Open Access Journals (Sweden)

    Aurelijus Daugėla


    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.

  11. Risk assessment of replacing conventional P fertilizers with biomass ash

    DEFF Research Database (Denmark)

    Cruz Paredes, Carla; Lopez Garcia, Alvaro; Rubæk, Gitte H.;


    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...

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

    DEFF Research Database (Denmark)

    Jensen, Peter Arendt

    technology a long range of research studies have been conducted, to improve our understanding of the influence and behavior of biomass ash species in suspension fired boilers. The fuel ash plays a key role with respect tooptimal boiler operation and influences phenomena’s as boiler chamber deposit formation......, corrosion of steam coils, deactivation of SCR catalysts and utilization of residual products. Abroad range of research tools as probe measurements on power plants, entrain flow reactorstudies and deposit modelling have been used to gain an improved understanding of ash transformation and ash deposit...... to generate ash particles typically in the size range of 50 to 200 μm on biomass suspension fired power plant boilers. A fragmentation rate of fuel particles of 3 have been used to describe both the residual ash formation process in laboratory entrained flow reactors and in full scale boilers.A range...

  13. Feeding by emerald ash borer larvae induces systemic changes in black ash foliar chemistry. (United States)

    Chen, Yigen; Whitehill, Justin G A; Bonello, Pierluigi; Poland, Therese M


    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.

  14. TIDD PFBC Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)


    In fluidized bed combustion, coal and sorbent (dolomite or limestone) are fed into a boiler in which air, entering from the bottom, maintains the bed material in a highly turbulent suspended state called fluidization. This turbulence creates good contact between the air and fuel, allowing for high combustion efficiency and excellent adsorption of sulfur dioxide (SO{sub 2}) during the combustion process. In PFBC applications, pressurized air is supplied to the combustor. Pressurizing the air concentrates a larger quantity of oxygen per unit volume. This results in a lower velocity of air through the fuel bed. The lower velocity reduces the total height required for the bed and freeboard above the bed. Also, a smaller plan area is required for the bed area as compared to an atmospheric fluidized bed. This has the advantage of requiring a much smaller pressure vessel to contain the boiler enclosure. The mean bed temperature of a pressurized fluidized bed combustor is typically maintained in the range 1540 to 1580 F. This is well below the ash fusion temperature of coal, yet above the ignition temperature of the coal. Advantages of the low bed temperature are no slag formation and a reduction of NO{sub x} emissions to less than half that of a conventional boiler. The Tidd Plant is a combined cycle pressurized fluidized bed combustion system with a topping gas cycle and a bottoming steam cycle.

  15. LIMB Demonstration Project Extension and Coolside Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Goots, T.R.; DePero, M.J.; Nolan, P.S.


    This report presents results from the limestone Injection Multistage Burner (LIMB) Demonstration Project Extension. LIMB is a furnace sorbent injection technology designed for the reduction of sulfur dioxide (SO[sub 2]) and nitrogen oxides (NO[sub x]) emissions from coal-fired utility boilers. The testing was conducted on the 105 Mwe, coal-fired, Unit 4 boiler at Ohio Edison's Edgewater Station in Lorain, Ohio. In addition to the LIMB Extension activities, the overall project included demonstration of the Coolside process for S0[sub 2] removal for which a separate report has been issued. The primary purpose of the DOE LIMB Extension testing, was to demonstrate the generic applicability of LIMB technology. The program sought to characterize the S0[sub 2] emissions that result when various calcium-based sorbents are injected into the furnace, while burning coals having sulfur content ranging from 1.6 to 3.8 weight percent. The four sorbents used included calcitic limestone, dolomitic hydrated lime, calcitic hydrated lime, and calcitic hydrated lime with a small amount of added calcium lignosulfonate. The results include those obtained for the various coal/sorbent combinations and the effects of the LIMB process on boiler and plant operations.

  16. Recovering germanium from coal ash by chlorination with ammonium chloride

    Institute of Scientific and Technical Information of China (English)


    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.

  17. Ash chemistry and sintering, verification of the mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Hupa, M.; Skrifvars, B.J. [Aabo Akademi, Turku (Finland)


    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)

  18. Improved prediction and tracking of volcanic ash clouds (United States)

    Webley, P.; Mastin, L.


    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.

  19. Reuse of Woody Biomass Ash Waste in Cementitious Materials


    Ukrainczyk, N.; Vrbos, N.; Koenders, E.A.B.


    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...

  20. Physical Parameters Affecting the Emanation of RADON-222 from Coal Ash. (United States)

    Barton, Terence Patrick

    . Emanation coefficient measurements of the pulverized ash at the moisture contents stated above ranged from 3.00 x 10('-3) to 1.56 x 10('-1) between 0 and 20 percent moisture, respectively. Both the stoker and the pulverized ashes demonstrated slight decreases in emanation coefficient between 20 and 40 percent moisture by weight. The effect of sample depth on observed emanation coefficient was assessed by measuring the emanation coefficient of five samples of ash each of four depths. Results of these measurements demonstrated no effect of depth on observed emanation coefficient.

  1. The Cement Solidification of Municipal Solid Waste Incineration Fly Ash

    Institute of Scientific and Technical Information of China (English)

    HOU Haobo; HE Xinghua; ZHU Shujing; ZHANG Dajie


    The chemical composition, the content and the leachability of heavy metals in municipal solid waste incineration ( MSWI) fly ash were tested and analyzed. It is shown that the leachability of Pb and Cr exceeds the leaching toxicity standard, and so the MSWI fly ash is considered as hazardous waste and must be solidifled. The effect of solidifying the MSWI fly ash by cement was studied, and it is indicated that the heavy metals can be well immobilized if the mass fraction of the fly ash is appropriate. The heavy metals were immobilized within cement hydration products through either physical fixation, substitution, deposition or adsorption mechanisms.

  2. Experimental Study on Volume for Fly Ash of Building Block

    Directory of Open Access Journals (Sweden)

    Ling Wang


    Full Text Available Fly ash is a waste substance from thermal power plants, steel mills, etc. That is found in abundance in the world. It has polluted the environment, wasting the cultivated land. This study introduces an experimental research on fly ash being reused effectively, the study introduces raw materials of fly ash brick, production process and product inspection, fly ash content could be amounted to 40%~75%. High doping fly ash bricks are manufactured, which selects wet fly ash from the power plants, adding aggregate with reasonable ratio and additives with reasonable dosage and do the experimental research on manufacture products for properties, production technology and selection about technology parameter of production equipment. Index of strength grade and freezing-thawing resisting etc and the high doping fly ash brick building which we are working on can achieve the national standard on building materials industry. Based on the tests, this achievement of research has a very wide practical prospect in using fly ash, industrial waste residue, environmental protection and reducing the cost of enterprises. The efficient reuse of fly ash from coal boiler and power plants has very vital significance of protecting the environment, benefiting descendants and developing of circular economy.

  3. Heavy metal characterization of circulating fluidized bed derived biomass ash. (United States)

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


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

  4. Environmental hazard of oil shale combustion fly ash. (United States)

    Blinova, Irina; Bityukova, Liidia; Kasemets, Kaja; Ivask, Angela; Käkinen, Aleksandr; Kurvet, Imbi; Bondarenko, Olesja; Kanarbik, Liina; Sihtmäe, Mariliis; Aruoja, Villem; Schvede, Hedi; Kahru, Anne


    The combined chemical and ecotoxicological characterization of oil shale combustion fly ash was performed. Ash was sampled from the most distant point of the ash-separation systems of the Balti and Eesti Thermal Power Plants in North-Eastern Estonia. The fly ash proved potentially hazardous for tested aquatic organisms and high alkalinity of the leachates (pH>10) is apparently the key factor determining its toxicity. The leachates were not genotoxic in the Ames assay. Also, the analysis showed that despite long-term intensive oil-shale combustion accompanied by considerable fly ash emissions has not led to significant soil contamination by hazardous trace elements in North-Eastern Estonia. Comparative study of the fly ash originating from the 'new' circulating fluidized bed (CFB) combustion technology and the 'old' pulverized-fired (PF) one showed that CFB fly ash was less toxic than PF fly ash. Thus, complete transfer to the 'new' technology will reduce (i) atmospheric emission of hazardous trace elements and (ii) fly ash toxicity to aquatic organisms as compared with the 'old' technology.

  5. Electrodialytic removal of cadmium from straw combustion fly ash

    DEFF Research Database (Denmark)

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


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

  6. Creep Behaviour of Fly Ash-Based Geopolymer Concrete



    Fly ash-based geopolymer concrete is manufactured using fly ash as its source material and does not use Portland cement at all. Beside fly ash, alkaline solution is also utilized to make geopolymer paste which binds the aggregates to form geopolymer concrete. This paper presents the study of creep behaviour of fly ash-based geopolymer concrete. Four series of specimens with various compressive strengths were prepared to study its creep behaviour for the duration of test up to one year. The te...

  7. Electrodialytic removal of Cd from biomass combustion fly ash

    DEFF Research Database (Denmark)

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


    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...... four ashes. Final Cd concentrations below 2.0 mg Cd/kg were reached in all ashes within 14 days of remediation and legislative requirements were met. After further optimization of the remediation process on the pre-washed straw ash, limiting concentrations were reached after only 48 hours...

  8. Assessing fly ash treatment: Remediation and stabilization of heavy metals

    KAUST Repository

    Lima, A.T.


    Fly ashes from Municipal Solid Waste (MSW), straw (ST) and co-combustion of wood (CW) are here analyzed with the intent of reusing them. Two techniques are assessed, a remediation technique and a solidification/stabilization one. The removal of heavy metals from fly ashes through the electrodialytic process (EDR) has been tried out before. The goal of removing heavy metals has always been the reuse of fly ash, for instance in agricultural fields (BEK). The best removal rates are here summarized and some new results have been added. MSW fly ashes are still too hazardous after treatment to even consider application to the soil. ST ash is the only residue that gets concentrations low enough to be reused, but its fertilizing value might be questioned. An alternative reuse for the three ashes is here preliminary tested, the combination of fly ash with mortar. Fly ashes have been substituted by cement fraction or aggregate fraction. Surprisingly, better compressive strengths were obtained by replacing the aggregate fraction. CW ashes presented promising results for the substitution of aggregate in mortar and possibly in concrete. © 2010 Elsevier Ltd.

  9. Geological behavior of wet outflow deposition fly ash

    Institute of Scientific and Technical Information of China (English)

    周德泉; 赵明华; 刘宏利; 周毅; 严聪


    The geological behaviors of wet outflow deposition fly ash were investigated, including the feature of in-situ single and even bridge cone penetration test (CPT) curves, the change of the penetration parameters and vane strength with the increase of depth and the difference of the penetration resistance on and down the water level. Drilling, CPT and vane shear test were carried out in silty clay, fine sand, and fly ash of the ash-dam. The CPT curves of the fly ash do not show a critical depth. The cone resistance (qc) of the fly ash is smaller than that of silty clay or sand; the friction resistance is smaller than that of filling silty clay, similar to that of deposition silty clay or more than that of fine sand; the friction ratio is smaller than that of filling silty clay, or more than that of deposition silty clay or much more than that of fine sand. The specific penetration resistance (ps) is similar to that of filling silty clay, or more than that of deposition silty clay. There is a clear interface effect between the deposition fly ash and the clay. Interface effect of ps-h curve at the groundwater table is clear, and ps of the fly ash reduces significantly under the table. The vane strength of the fly ash increases as the depth increases. The deposition fly ash with wet outflow is similar to silt in the geological behavior.

  10. Effect of refractory agent on ash fusibility temperatures of briquette

    Institute of Scientific and Technical Information of China (English)

    Guo-xing CUI; Kui HUANG; Ming-sui LIN


    To solve the problem of the low ash fusion point of briquette,this paper reported that the ash fusibility temperatures can be elevated by changing ash ingredients through blending refractory agents in briquette ash,which will create favorable conditions for moving bed continuous gasification of briquette with oxygen-rich air.The effects of Al2O3,SiO2,kaolin,dry powder and bentonite on ash fusibility temperatures were studied,based upon the relationship between briquette ash components and ash fusibility.The results show that the increasing of ash fusibility temperatures by adding the same amount (11%,w)of refractory agents follows the sequence of SiO2,bentonite,dry powder,kaolin,Al2O3,with the softening temperatures beingelevated by 37.2,57.6,60.4,82.6 and 104.4 ℃.With the same ratio of SiO2/Al2O3 in briquette,adding the Al2O3 component is more effective than SiO2 for raising ash fusibility temperatures.In this paper,inexpensive kaolin and bentonite rich in Al2O3 are found to be better refractory agents,and the suitable adding quantities are 9% and 11%,respectively.

  11. Surface Modification of Fly Ash for Active Catalysis

    Directory of Open Access Journals (Sweden)

    Deepti Jain


    Full Text Available Fly ash based effective solid base catalyst (KF/Al2O3/fly ash473, KF/Al2O3/fly ash673, and KF/Al2O3/fly ash873 was synthesized by loading KF over chemically and thermally activated fly ash. The chemical activation was done by treating fly ash with aluminum nitrate via precipitation method followed by thermal activation at 650°C to increase the alumina content in fly ash. The increased alumina content was confirmed by SEM-EDX analysis. The alumina enriched fly ash was then loaded with KF (10 wt% and calcined at three different temperatures 473 K, 673 K and 873 K. The amount of loaded KF was monitored by XRD, FTIR spectroscopy, SEM-EDX, TEM and Flame Atomic Absorption Spectrophotometer. The catalytic activities of the catalysts were tested in the Claisen-Schmidt condensation of benzaldehyde and 4-methoxybenzaldehyde with 2′-hydroxyacetophenone to produce 2′-hydroxychalcone and 4-methoxy-2′-hydroxychalcone respectively. Higher conversion (83% of benzaldehyde and (89% of 4-methoxybenzaldehyde reveals that among these heterogeneous catalysts KF/Al2O3/fly ash673 is very active.

  12. Utilisation of coal ash to improve acid soil

    Directory of Open Access Journals (Sweden)

    Shigeru Kato


    Full Text Available The study on utilization of coal ash to improve acid soil was carried out in a greenhouse at the Land Development Regional Office 1, Pathum Thani Province, Central Thailand, from January-May 2003. Fly ash mixture (fly ash plus gypsum and lime at the proportion 5:4:1 and clinker ash mixture (clinker ash plus gypsum and lime at the proportion 5:4:1 were used as soil amendments at varying rates i.e., 0, 6.25,12.5, 18.75 and 25 t/ha to improve the soil. The aim of this study was to determine the effect of application of coal ash on acid soil and the growth of a vegetable (Chinese kale. Chinese kale cultivars were planted in a randomized complete block design with three replications. Pak Chong soil series (Ultisols was used as the growth medium. Twenty-day-old seedlings were transplanted in 270 pots (two plants per pot containing acid soil with different treatments of coal ash mixture which were as follows: 1 control, 2 fly ash mixture 6.25 t/ha, 3 fly ash mixture 12.5 t/ha, 4 fly ash mixture 18.75 t/ha, 5 fly ash mixture 25 t/ha, 6 clinker ash mixture 6.25 t/ha, 7 clinker ash mixture 12.5 t/ha, 8 clinker ash mixture 18.75 t/ha and 9 clinker ash mixture 25 t/ha. Chemical fertilizers were applied at the rate of 250 kg/ha using a grade of 15-15-15 of N, P and K, respectively. Plants were harvested 40 days after transplanting. Among the treatments, application of fly ashmixture at a rate of 25t/ha (4t/rai substantially increased soil pH up to 5.7. Fly ash was found more effective than clinker ash in increasing soil pH. The highest yield of Chinese kale was also obtained when fly ash mixture was applied at a rate of 25 t/ha followed by fly ash mixture at 18.75 t/ha and clinker ash mixture at 18.75 t/ha with an average yield per plant of 4.980, 3.743 and 3.447 grams, respectively. It can be concluded that the application of coal ash mixture, either fly- or clinker ash, at 18.75-25 t/ha (3-4 t/rai was the most effective in terms of plant yield. The use of

  13. JV Task 120 - Coal Ash Resources Research Consortium Research

    Energy Technology Data Exchange (ETDEWEB)

    Debra Pflughoeft-Hassett; Loreal Heebink; David Hassett; Bruce Dockter; Kurt Eylands; Tera Buckley; Erick Zacher


    . Special projects provide an opportunity for non-CARRC members to sponsor specific research or technology transfer consistent with CARRC goals. This report covers CARRC activities from January 2007 through March 2009. These activities have been reported in CARRC Annual Reports and in member meetings over the past 2 years. CARRC continues to work with industry and various government agencies with its research, development, demonstration, and promotional activities nearing completion at the time of submission of this report. CARRC expects to continue its service to the coal ash industry in 2009 and beyond to work toward the common goal of advancing coal ash utilization by solving CCP-related technical issues and promoting the environmentally safe, technically sound, and economically viable management of these complex and changing materials.

  14. Integrated acid mine drainage management using fly ash. (United States)

    Vadapalli, Viswanath R K; Gitari, Mugera W; Petrik, Leslie F; Etchebers, Olivier; Ellendt, Annabelle


    Fly Ash (FA) from a power station in South Africa was investigated to neutralise and remove contaminants from Acid Mine Drainage (AMD). After this primary treatment the insoluble FA residue namely solid residue (SR) was investigated as a suitable mine backfill material by means of strength testing. Moreover, SR was used to synthesise zeolite-P using a two-step synthesis procedure. Furthermore, the zeolite-P was investigated to polish process water from the primary FA-AMD reaction. The main objective of this series of investigations is to achieve zero waste and to propose an integrated AMD management using FA. Fly Ash was mixed with AMD at various predetermined FA-AMD ratios until the mixtures achieved circumneutral pH or higher. The supernatants were then analyzed using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Ion Chromatography (IC) for cations and anions respectively. The physical strength testing of SR was carried out by mixing it with 3% Ordinary Portland Cement (OPC) and curing for 410 days. Synthesis of zeolite-P using SR was carried out by two step synthesis procedure: ageing for 24 hours followed by a mild hydrothermal synthesis at 100°C for 4 days. The polishing of process water from primary AMD treatment using FA was ascertained by mixing the process water with zeolite at a liquid to solid ratio of 100:1 for 1 hour. The results indicated that FA can be successfully used to ameliorate AMD. High removal of major AMD contaminants Fe, Al, Mg, Mn and sulphate was achieved with the ash treatment and trace elements such as Zn, Ni, Cu and Pb were also removed by the FA. Strength testing over 410 days indicated that the material gained strength over the testing period. The maximum unconfined compressive strength and elastic modulus was observed to be approximately 0.3 MPa and 150 Mpa respectively. The X-ray diffraction (XRD) analysis of the synthesized product indicated that SR was successfully converted into zeolite-P with some mullite phase

  15. Corrosion of steel bars in cracked concrete made with ordinary portland, slag and fly ash cements

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, T.U.; Yamaji, T.; Hamada, H. [Port and Harbor Research Inst., Ministry of Land, Infrastructure and Transport (Japan); Aoyama, T. [PS Corp. (Japan)


    A study was conducted in which the marine durability of ordinary portland cement, slag and fly ash cement was examined using 15 year old plain and reinforced concrete cylindrical specimens. The performance of these cements was then examined for pre-cracked reinforced concrete prism samples. The process of manufacturing cement emits huge amounts of carbon dioxide into the global atmosphere. Replacing a portion of the cement with by-products from the steel industry and thermal power plants (which are both huge emitters of carbon dioxide) can lower carbon dioxide emissions and also solve the disposal issue of slag and fly ash while increasing the long-term durability of concrete structures. In this study, concrete cylindrical specimens were made of ordinary portland cement, slag and fly ash cements. The specimens were 100 x 100 x 600 mm prisms of different types of cement. Water-to-cement ratios were 0.45 and 0.55. Both tap water and seawater were used as mixing water. The samples were exposed in tidal pools for 15 years to evaluate the compressive strength of the concrete, corrosion of the steel bars, and chloride-ion concentrations in the concrete. It was shown that, with the exception of fly ash cements, the compressive strength of most cements increased after 15 years of exposure compared to its 28 day strength. Type C slag cement demonstrated the best performance against chloride-ion at the surface of concrete made with slag and fly ash. Voids in the steel-concrete interface make it possible for corrosion pits to develop. The use of seawater as mixing water results in earlier strength development at 28 days and does not cause to the strength of the concrete to regress after 15-years of exposure, but it causes more corrosion of steel bars at a lower cover depth. Corrosion of steel bars is not an issue at deeper cover depths. 15 refs., 19 tabs., 13 figs.

  16. Whole-coal versus ash basis in coal geochemistry: a mathematical approach to consistent interpretations (United States)

    Geboy, Nicholas J.; Engle, Mark A.; Hower, James C.


    Several standard methods require coal to be ashed prior to geochemical analysis. Researchers, however, are commonly interested in the compositional nature of the whole-coal, not its ash. Coal geochemical data for any given sample can, therefore, be reported in the ash basis on which it is analyzed or the whole-coal basis to which the ash basis data are back calculated. Basic univariate (mean, variance, distribution, etc.) and bivariate (correlation coefficients, etc.) measures of the same suite of samples can be very different depending which reporting basis the researcher uses. These differences are not real, but an artifact resulting from the compositional nature of most geochemical data. The technical term for this artifact is subcompositional incoherence. Since compositional data are forced to a constant sum, such as 100% or 1,000,000 ppm, they possess curvilinear properties which make the Euclidean principles on which most statistical tests rely inappropriate, leading to erroneous results. Applying the isometric logratio (ilr) transformation to compositional data allows them to be represented in Euclidean space and evaluated using traditional tests without fear of producing mathematically inconsistent results. When applied to coal geochemical data, the issues related to differences between the two reporting bases are resolved as demonstrated in this paper using major oxide and trace metal data from the Pennsylvanian-age Pond Creek coal of eastern Kentucky, USA. Following ilr transformation, univariate statistics, such as mean and variance, still differ between the ash basis and whole-coal basis, but in predictable and calculated manners. Further, the stability between two different components, a bivariate measure, is identical, regardless of the reporting basis. The application of ilr transformations addresses both the erroneous results of Euclidean-based measurements on compositional data as well as the inconsistencies observed on coal geochemical data

  17. Rheological analysis of an effect of different deflocculants on the fly-ash slurry (United States)

    Sarnecki, K.; Bartosik, A.


    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.

  18. A model for wet aggregation of ash particles in volcanic plumes and clouds: 2. Model application (United States)

    Folch, A.; Costa, A.; Durant, A.; Macedonio, G.


    The occurrence of particle aggregation has a dramatic effect on the transport and sedimentation of volcanic ash. The aggregation process is complex and can occur under different conditions and in multiple regions of the plume and in the ash cloud. In the companion paper, Costa et al. develop an aggregation model based on a fractal relationship to describe the rate particles are incorporated into ash aggregates. The model includes the effects of both magmatic and atmospheric water present in the volcanic cloud and demonstrates that the rate of aggregation depends on the characteristics of the initial particle size distribution. The aggregation model includes two parameters, the fractal exponent Df, which describes the efficiency of the aggregation process, and the aggregate settling velocity correction factor ψe, which influences the distance at which distal mass deposition maxima form. Both parameters are adjusted using features of the observed deposits. Here this aggregation model is implemented in the FALL3D volcanic ash transport model and applied to the 18 May 1980 Mount St. Helens and the 17-18 September 1992 Crater Peak eruptions. For both eruptions, the optimized values for Df (2.96-3.00) and ψe (0.27-0.33) indicate that the ash aggregates had a bulk density of 700-800 kg m-3. The model provides a higher degree of agreement than previous fully empirical aggregation models and successfully reproduces the depositional characteristics of the deposits investigated over a large range of scales, including the position and thickness of the secondary maxima.

  19. The Early Detection of the Emerald Ash Borer (EAB) Using Advanced Geospacial Technologies (United States)

    Hu, B.; Li, J.; Wang, J.; Hall, B.


    The objectives of this study were to exploit Light Detection And Ranging (LiDAR) and very high spatial resolution (VHR) data and their synergy with hyperspectral imagery in the early detection of the EAB presence in trees within urban areas and to develop a framework to combine information extracted from multiple data sources. To achieve these, an object-oriented framework was developed to combine information derived from available data sets to characterize ash trees. Within this framework, individual trees were first extracted and then classified into different species based on their spectral information derived from hyperspectral imagery, spatial information from VHR imagery, and for each ash tree its health state and EAB infestation stage were determined based on hyperspectral imagery. The developed framework and methods were demonstrated to be effective according to the results obtained on two study sites in the city of Toronto, Ontario Canada. The individual tree delineation method provided satisfactory results with an overall accuracy of 78 % and 19 % commission and 23 % omission errors when used on the combined very high-spatial resolution imagery and LiDAR data. In terms of the identification of ash trees, given sufficient representative training data, our classification model was able to predict tree species with above 75 % overall accuracy, and mis-classification occurred mainly between ash and maple trees. The hypothesis that a strong correlation exists between general tree stress and EAB infestation was confirmed. Vegetation indices sensitive to leaf chlorophyll content derived from hyperspectral imagery can be used to predict the EAB infestation levels for each ash tree.

  20. Nutritional attributes of ash (Fraxinus spp.) outer bark and phloem and their relationships to resistance against the emerald ash borer. (United States)

    Hill, Amy L; Whitehill, Justin G A; Opiyo, Stephen O; Phelan, P Larry; Bonello, Pierluigi


    The emerald ash borer (Agrilus planipennis Fairmaire, EAB) is an alien, invasive wood-boring insect that is responsible for killing millions of ash trees since its discovery in North America in 2002. All North American ash species (Fraxinus spp.) that EAB has encountered have shown various degrees of susceptibility, while Manchurian ash (Fraxinus mandshurica Ruprecht), which shares a co-evolutionary history with this insect, is resistant. Recent studies have looked into constitutive resistance mechanisms in Manchurian ash, concentrating on the secondary phloem, which is the feeding substrate for the insect. In addition to specialized metabolism and defense-related components, primary metabolites and nutritional summaries can also be important to understand the feeding behavior of insect herbivores. Here, we have compared the nutritional characteristics (water content, total protein, free amino acids, total soluble sugars and starch, percent carbon and nitrogen, and macro- and micronutrients) of outer bark and phloem from black, green, white and Manchurian ash to determine their relevance to resistance or susceptibility to EAB. Water content and concentrations of Al, Ba, Cu, Fe, K, Li, tryptophan and an unknown compound were found to separate black and Manchurian ash from green and white ash in a principal component analysis (PCA), confirming their phylogenetic placements into two distinct clades. The traits that distinguished Manchurian ash from black ash in the PCA were water content and concentrations of total soluble sugars, histidine, lysine, methionine, ornithine, proline, sarcosine, tyramine, tyrosol, Al, Fe, K, Na, V and an unknown compound. However, only proline, tyramine and tyrosol were significantly different, and higher, in Manchurian ash than in black ash.

  1. The slippery slope: how small ethical transgressions pave the way for larger future transgressions. (United States)

    Welsh, David T; Ordóñez, Lisa D; Snyder, Deirdre G; Christian, Michael S


    Many recent corporate scandals have been described as resulting from a slippery slope in which a series of small infractions gradually increased over time (e.g., McLean & Elkind, 2003). However, behavioral ethics research has rarely considered how unethical behavior unfolds over time. In this study, we draw on theories of self-regulation to examine whether individuals engage in a slippery slope of increasingly unethical behavior. First, we extend Bandura's (1991, 1999) social-cognitive theory by demonstrating how the mechanism of moral disengagement can reduce ethicality over a series of gradually increasing indiscretions. Second, we draw from recent research connecting regulatory focus theory and behavioral ethics (Gino & Margolis, 2011) to demonstrate that inducing a prevention focus moderates this mediated relationship by reducing one's propensity to slide down the slippery slope. We find support for the developed model across 4 multiround studies.

  2. Durability of biomass fly ash concrete: Freezing and thawing and rapid chloride permeability tests

    Energy Technology Data Exchange (ETDEWEB)

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


    Strict interpretation of ASTM C 618 excludes non-coal fly ashes, such as biomass fly ashes from addition in concrete. Biomass fly ash in this investigation includes (1) cofired fly ash from burning biomass with coal; (2) wood fly ash and (3) blended fly ash (wood fly ash mixing with coal fly ash). A set of experiments conducted on concrete from pure cement and cement with fly ash provide basic data to assess the effects of several biomass fly ashes on the performances of freezing and thawing (F-T) and rapid chloride permeability test (RCPT). The F-T tests indicate that all fly ash concrete has statistically equal or less weight loss than the pure cement concrete (control). The RCPT illustrate that all kinds of fly ash concrete have lower chloride permeability than the pure cement control concrete. 37 refs., 5 figs.

  3. Gas generation in incinerator ash; Gasbildning i aska

    Energy Technology Data Exchange (ETDEWEB)

    Arm, Maria; Lindeberg, Johanna; Rodin, Aasa; Oehrstroem, Anna; Backman, Rainer; Oehman, Marcus; Bostroem, Dan


    In recent years, explosions have occurred in certain phases of ash handling in Sweden. Investigations have revealed that hydrogen may have been present in all cases. The hydrogen is believed to be generated by chemical reactions of aluminium and other metals within the ash in the presence of water. The purpose with this study is to increase the knowledge of gas generation of incinerator ash. Thereby, guides for appropriate ash management can be introduced and the risk for further explosions prevented. The study has comprised analyses of the ash properties, such as chemical and physical composition and the pH, of ash from 14 incineration plants (mostly waste incineration plants). Different fractions of ash materials representing different parts of the process in each plant have been analysed. Furthermore, the fuel and the technical differences between the plants have been analysed. A tool for measuring the gas generation in the laboratory has been developed and the gas generation of the different ash materials at natural and increased pH was measured. Gas analyses and thermodynamic calculations have also been performed. The results showed that: bottom ash from fluidised bed boilers generated small amounts of gas at increased pH, much smaller amounts than the idle pass, cyclone and filter ash did, bottom ash from grate fired boilers generated more gas at increased pH than their cyclone ash and filter ash, with exception of the Linkoeping plant, all bio waste incineration plants generated ash with low gas generation potential, all fly ash materials with a gas generation potential of more than 10 l/kg originated from municipal waste incineration plants, filter ash that had been stored in oxygen rich environment generated significant less gas than fresh filter ash of the same origin, hardly any other gases were generated apart from hydrogen (very small amounts of acetone, furane, benzene and most likely methane were detected in some of the ash materials), there were no

  4. Effects of water availability on emerald ash borer larval performance and phloem phenolics of Manchurian and black ash. (United States)

    Chakraborty, Sourav; Whitehill, Justin G A; Hill, Amy L; Opiyo, Stephen O; Cipollini, Don; Herms, Daniel A; Bonello, Pierluigi


    The invasive emerald ash borer (EAB) beetle is a significant threat to the survival of North American ash. In previous work, we identified putative biochemical and molecular markers of constitutive EAB resistance in Manchurian ash, an Asian species co-evolved with EAB. Here, we employed high-throughput high-performance liquid chromatography with photodiode array detection and mass spectrometry (HPLC-PDA-MS) to characterize the induced response of soluble phloem phenolics to EAB attack in resistant Manchurian and susceptible black ash under conditions of either normal or low water availability, and the effects of water availability on larval performance. Total larval mass per tree was lower in Manchurian than in black ash. Low water increased larval numbers and mean larval mass overall, but more so in Manchurian ash. Low water did not affect levels of phenolics in either host species, but six phenolics decreased in response to EAB. In both ashes, pinoresinol A was induced by EAB, especially in Manchurian ash. Pinoresinol A and pinoresinol B were negatively correlated with each other in both species. The higher accumulation of pinoresinol A in Manchurian ash after attack may help explain the resistance of this species to EAB, but none of the responses measured here could explain increased larval performance in trees subjected to low water availability.

  5. Coal Ash Corrosion Resistant Materials Testing

    Energy Technology Data Exchange (ETDEWEB)

    D. K. McDonald; P. L. Daniel; D. J. DeVault


    In April 1999, three identical superheater test sections were installed into the Niles Unit No.1 for the purpose of testing and ranking the coal ash corrosion resistance of candidate superheater alloys. The Niles boiler burns high sulfur coal (3% to 3.5%) that has a reasonably high alkali content, thus the constituents necessary for coal ash corrosion are present in the ash. The test sections were controlled to operate with an average surface metal temperature from approximately 1060 F to 1210 F which was well within the temperature range over which coal ash corrosion occurs. Thus, this combination of aggressive environment and high temperature was appropriate for testing the performance of candidate corrosion-resistant tube materials. Analyses of the deposit and scale confirmed that the aggressive alkali-iron-trisulfate constituent was present at the metal surface and active in tube metal wastage. The test sections were constructed so that the response of twelve different candidate tube and/or coating materials could be studied. The plan was to remove and evaluate one of the three test sections at time intervals of 1 year, 3 years, and 5 years. This would permit an assessment of performance of the candidate materials as a function of time. This report provides the results of the evaluation of Test Section C, including the samples that remained in the Test Section for the full exposure period as well as those that were removed early. The analysis of Test Section C followed much the same protocol that was employed in the assessment of Test Section A. Again, the focus was on determining and documenting the relative corrosion rates of the candidate materials. The detailed results of the investigation are included in this report as a series of twelve appendices. Each appendix is devoted to the performance of one of the candidate alloys. The table below summarizes metal loss rate for the worst case sample of each of the candidate materials for both Test Sections A and C

  6. NUCLA Circulating Atmospheric Fluidized Bed Demonstration Project

    Energy Technology Data Exchange (ETDEWEB)

    Keith, Raymond E.; Heller, Thomas J.; Bush, Stuart A.


    This Annual Report on Colorado-Ute Electric Association's NUCLA Circulating Fluidized Bed (CFB) Demonstration Program covers the period from February 1987 through December 1988. The outline for presentation in this report includes a summary of unit operations along with individual sections covering progress in study plan areas that commenced during this reporting period. These include cold-mode shakedown and calibration, plant commercial performance statistics, unit start-up (cold), coal and limestone preparation and handling, ash handling system performance and operating experience, tubular air heater, baghouse operation and performance, materials monitoring, and reliability monitoring. During this reporting period, the coal-mode shakedown and calibration plan was completed. (VC)

  7. The POSEIDON Demonstrator

    NARCIS (Netherlands)

    Laar, P.J.L.J. van de


    In this chapter, we discuss the Poseidon demonstrator: a demonstrator that integrates the individual research results of all partners of the Poseidon project. After describing how the Poseidon demonstrator was built, deployed, and operated, we will not only show many results obtained from the demons

  8. Overhead Projector Demonstrations. (United States)

    Kolb, Doris, Ed.


    Details two demonstrations for use with an overhead projector in a chemistry lecture. Includes "A Very Rapidly Growing Silicate Crystal" and "A Colorful Demonstration to Simulate Orbital Hybridization." The materials and directions for each demonstration are included as well as a brief explanation of the essential learning involved. (CW)

  9. Interspecific comparison of constitutive ash phloem phenolic chemistry reveals compounds unique to manchurian ash, a species resistant to emerald ash borer. (United States)

    Whitehill, Justin G A; Opiyo, Stephen O; Koch, Jennifer L; Herms, Daniel A; Cipollini, Donald F; Bonello, Pierluigi


    The emerald ash borer (Agrilus planipennis, EAB) is an invasive wood-borer indigenous to Asia and is responsible for widespread ash (Fraxinus spp.) mortality in the U.S. and Canada. Resistance and susceptibility to EAB varies among Fraxinus spp., which is a result of their co-evolutionary history with the pest. We characterized constitutive phenolic profiles and lignin levels in the phloem of green, white, black, blue, European, and Manchurian ash. Phloem was sampled twice during the growing season, coinciding with phenology of early and late instar EAB. We identified 66 metabolites that displayed a pattern of variation, which corresponded strongly with phylogeny. Previously identified lignans and lignan derivatives were confirmed to be unique to Manchurian ash, and may contribute to its high level of resistance to EAB. Other compounds that had been considered unique to Manchurian ash, including hydroxycoumarins and the phenylethanoids calceolarioside A and B, were detected in closely related, but susceptible species, and thus are unlikely to contribute to EAB resistance of Manchurian ash. The distinct phenolic profile of blue ash may contribute to its relatively high resistance to EAB.

  10. Sulfate resistance of ordinary Portland cement with fly ash

    Directory of Open Access Journals (Sweden)

    Irassar, Edgardo F.


    Full Text Available Low calcium fly ash has demonstrated to be an effective pozzolan to improve sulfate resistance of ordinary portland cement (type I. In this paper physico-chemical effects that produce this pozzolan in the mortar exposed to sulfate attack are studied. Dilution and dispersion affects are analyzed using mixes of cement with an inert mineral admixture. Mineralogical changes of mortar are studied using X-ray diffraction and the help of scanning electron microscope. The results show that fly ash delays mortar cracking phenomenon due to less content of unstable compounds in sulfate environment, greater available space to be occupied by expansive compounds and less CH present in the mortars.

    La ceniza volante de bajo contenido de óxido de calcio ha demostrado ser una efectiva puzolana para mejorar la resistencia a los sulfatos del cemento portland normal (CRN. En el presente trabajo se estudian los efectos físico-químicos que produce esta puzolana en el mortero expuesto al ataque de sulfatos. Se analizan los efectos de dilución y dispersión utilizando mezclas de cemento con una adición mineral inactiva. Los cambios mineralógicos del mortero se estudian con difracción de rayos X (DRX y la ayuda del microscopio electrónico. Los resultados indican que la ceniza volante retarda el fenómeno de fisuración del mortero debido a la menor cantidad de compuestos inestables en ambiente con sulfatos, el mayor espacio disponible para albergar a los compuestos expansivos y la disminución del CH presente en la mezcla.

  11. Synthesis of ZSM-5 zeolite from lignite fly ash and rice husk ash

    Energy Technology Data Exchange (ETDEWEB)

    Chareonpanich, Metta; Namto, Teerapong; Kongkachuichay, Paisan [Department of Chemical Engineering, Kasetsart University, 50 Paholyothin Rd., Chatuchak, Bangkok 10900 (Thailand); Limtrakul, Jumras [Department of Chemistry, Kasetsart University, Chatuchak, Bangkok 10900 (Thailand)


    The lignite fly ash from the Mae-Moh power plant, Thailand, and rice husk ash were used as raw materials for ZSM-5 zeolite synthesis. Factors affecting the yield of ZSM-5 zeolite synthesized from fly ash, i.e., the SiO{sub 2}/Al{sub 2}O{sub 3} mole ratio, the presence of tetrapropyl ammonium bromide (TPABr, the structure-directing material for ZSM-5 zeolite synthesis), the holding temperature and time, and the initial pressure were investigated. It was found that without TPABr only zeolite P could be synthesized at SiO{sub 2}/Al{sub 2}O{sub 3} mole ratios of 2.8-200. In order to synthesize ZSM-5 zeolite, sodium silicate solution was added to adjust the SiO{sub 2}/Al{sub 2}O{sub 3} mole ratio in raw ash. The yield of ZSM-5 zeolite was as high as 59 wt.% when following conditions were used: SiO{sub 2}/Al{sub 2}O{sub 3} mole ratio, 40; the holding temperature, 210 C; the holding time, 4 h and the initial pressure, 4 bar. The catalytic performance for CO{sub 2} hydrogenation reaction of the ZSM-5 zeolite was preliminary tested and compared with that of commercial one. It was observed that there was no significant difference in the catalytic performance between these two catalysts.

  12. Illinois basin coal fly ashes. 2. Equilibria relationships and qualitative modeling of ash-water reactions (United States)

    Roy, W.R.; Griffin, R.A.


    Alkaline and acidic Illinois Basin coal fly ash samples were each mixed with deionized water and equilibrated for about 140 days to simulate ash ponding environments. Common to both equilibrated solutions, anhydrite solubility dominated Ca2+ activities, and Al3+ activities were in equilibrium with both matrix mullite and insoluble aluminum hydroxide phases. Aqueous silica activities were controlled by both mullite and matrix silicates. The pH of the extract of the acidic fly ash was 4.1 after 24 h but increased to a pH value of 6.4 as the H2SO4, assumed to be adsorbed to the particle surfaces, was exhausted by the dissolution of matrix iron oxides and aluminosilicates. The activities of aqueous Al3+ and iron, initially at high levels during the early stages of equilibration, decreased to below analytical detection limits as the result of the formation of insoluble Fe and Al hydroxide phases. The pH of the extract of the alkaline fly ash remained above a pH value of 10 during the entire equilibration interval as a result of the hydrolysis of matrix oxides. As with the acidic system, Al3+ activities were controlled by amorphous aluminum hydroxide phases that began to form after about 7 days of equilibration. The proposed mechanisms and their interrelations are discussed in addition to the solubility diagrams used to deduce these relationships. ?? 1984 American Chemical Society.

  13. Synergic Effect of Wheat Straw Ash and Rice-Husk Ash on Strength Properties of Mortar (United States)

    Goyal, Ajay; Kunio, Hattori; Ogata, Hidehiko; Garg, Monika; Anwar, A. M.; Ashraf, M.; Mandula

    Pozzolan materials obtained from various sources; when used as partial replacement for Portland cement in cement based applications play an important role not only towards sustainable development but in reducing the construction costs as well. Present study was conducted to investigate the synergic effect of Rice-Husk Ash (RHA) and Wheat Straw Ash (WSA) on the strength properties of ash substituted mortar. Ash materials were obtained after burning the wastes at 600°C for 5 h at a control rate of 2°C min. Two binary blends of mortar substituting 15% cement with WSA and RHA and three combinations of ternary blend with (10+5)%, (5+10)% and (7.5+7.5)% mix ratios of WSA and RHA, together with a control specimen were subjected to destructive (compressive and flexural strength) as well as non-destructive (ultrasonic pulse velocity) tests till 180 days of curing. Ternary blend with (7.5 + 7.5)% combination of WSA and RHA showed better strength results than control and other blends and proved to be the optimum combination for achieving maximum synergic effect.

  14. 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


    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...

  15. Spectral analysis of white ash response to emerald ash borer infestations (United States)

    Calandra, Laura

    The emerald ash borer (EAB) (Agrilus planipennis Fairmaire) is an invasive insect that has killed over 50 million ash trees in the US. The goal of this research was to establish a method to identify ash trees infested with EAB using remote sensing techniques at the leaf-level and tree crown level. First, a field-based study at the leaf-level used the range of spectral bands from the WorldView-2 sensor to determine if there was a significant difference between EAB-infested white ash (Fraxinus americana) and healthy leaves. Binary logistic regression models were developed using individual and combinations of wavelengths; the most successful model included 545 and 950 nm bands. The second half of this research employed imagery to identify healthy and EAB-infested trees, comparing pixel- and object-based methods by applying an unsupervised classification approach and a tree crown delineation algorithm, respectively. The pixel-based models attained the highest overall accuracies.

  16. Experimental demonstration of coupled optical springs (United States)

    Gordon, N. A.; Barr, B. W.; Bell, A.; Graef, C.; Hild, S.; Huttner, S. H.; Leavey, S. S.; Macarthur, J.; Sorazu, B.; Wright, J.; Strain, K. A.


    Optical rigidity will play an important role in improving the sensitivity of future generations of gravitational wave (GW) interferometers, which employ high laser power in order to reach and exceed the standard quantum limit. Several experiments have demonstrated the combined effect of two optical springs on a single system for very low-weight mirror masses or membranes. In this paper we investigate the complex interactions between multiple optical springs and the surrounding apparatus in a system of comparable dynamics to a large-scale GW detector. Using three 100 g mirrors to form a coupled cavity system capable of sustaining two or more optical springs, we demonstrate a number of different regimes of opto-mechanical rigidity and measurement techniques. Our measurements reveal couplings between each optical spring and the control loops that can affect both the achievable increase in sensitivity and the stability of the system. Hence this work establishes a better understanding of the realisation of these techniques and paves the way to their application in future GW observatories, such as upgrades to Advanced LIGO.

  17. Optical Properties of Volcanic Ash: Improving Remote Sensing Observations (United States)

    Whelley, P.; Colarco, P. R.; Aquila, V.; Krotkov, N. A.; Bleacher, J. E.; Garry, W. B.; Young, K. E.; Lima, A. R.; Martins, J. V.; Carn, S. A.


    Many times each year explosive volcanic eruptions loft ash into the atmosphere. Global travel and trade rely on aircraft vulnerable to encounters with airborne ash. Volcanic ash advisory centers (VAACs) rely on dispersion forecasts and satellite data to issue timely warnings. To improve ash forecasts model developers and satellite data providers need realistic information about volcanic ash microphysical and optical properties. In anticipation of future large eruptions we can study smaller events to improve our remote sensing and modeling skills so when the next Pinatubo 1991 or larger eruption occurs, ash can confidently be tracked in a quantitative way. At distances >100km from their sources, drifting ash plumes, often above meteorological clouds, are not easily detected from conventional remote sensing platforms, save deriving their quantitative characteristics, such as mass density. Quantitative interpretation of these observations depends on a priori knowledge of the spectral optical properties of the ash in UV (>0.3μm) and TIR wavelengths (>10μm). Incorrect assumptions about the optical properties result in large errors in inferred column mass loading and size distribution, which misguide operational ash forecasts. Similarly, simulating ash properties in global climate models also requires some knowledge of optical properties to improve aerosol speciation. Recent research has identified a wide range in volcanic ash optical properties among samples collected from the ground after different eruptions. The database of samples investigated remains relatively small, and measurements of optical properties at the relevant particle sizes and spectral channels are far from complete. Generalizing optical properties remains elusive, as does establishing relationships between ash composition and optical properties, which are essential for satellite retrievals. We are building a library of volcanic ash optical and microphysical properties. In this presentation we show

  18. Extraction of vanadium from athabasca tar sands fly ash (United States)

    Gomez-Bueno, C. O.; Spink, D. R.; Rempel, G. L.


    The production of refinery grade oil from the Alberta tar sands deposits as currently practiced by Suncor (formally Great Canadian Oil Sands Ltd.—GCOS) generates a substantial amount of petroleum coke fly ash which contains appreciable amounts of valuable metals such as vanadium, nickel and titanium. Although the recovery of vanadium from petroleum ash is a well established commercial practice, it is shown in the present work that such processes are not suitable for recovery of vanadium from the GCOS fly ash. The fact that the GCOS fly ash behaves so differently when compared to other petroleum fly ash is attributed to its high silicon and aluminum contents which tie up the metal values in a silica-alumina matrix. Results of experiments carried out in this investigation indicate that such matrices can be broken down by application of a sodium chloride/water roast of the carbon-free fly ash. Based on results from a series of preliminary studies, a detailed investigation was undertaken in order to define optimum conditions for a vanadium extraction process. The process developed involves a high temperature (875 to 950 °C) roasting of the fly ash in the presence of sodium chloride and water vapor carried out in a rotary screw kiln, followed by dilute sodium hydroxide atmosphereic leaching (98 °C) to solublize about 85 pet of the vanadium originally present in the fly ash. It was found that the salt roasting operation, besides enhancing vanadium recovery, also inhibits silicon dissolution during the subsequent leaching step. The salt roasting treatment is found to improve vanadium recovery significantly when the fly ash is fully oxidized. This is easily achieved by burning off the carbon present in the “as received” fly ash under excess air. The basic leaching used in the new process selectively dissolves vanadium from the roasted ash, leaving nickel and titanium untouched.

  19. Total lead (Pb) concentration in oil shale ash samples based on correlation to isotope Pb-210 gamma-spectrometric measurements

    Energy Technology Data Exchange (ETDEWEB)

    Vaasma, T.; Kiisk, M.; Tkaczyk, A.H. [University of Tartu (Estonia); Bitjukova, L. [Tallinn University of Technology (Estonia)


    (PF) and circulating fluidized bed (CFB) firing technology. These samples were analyzed to determine macro and trace elements by the ICP-MS method. The same samples were also measured with a high-purity germanium detector (planar BSI GPD-50400) to determine the activity concentrations of natural radionuclides. The lead concentrations and Pb-210 activity concentrations were determined, and the correlation between the corresponding values was analyzed. Initial results demonstrate a strong positive linear relationship between these values, with the coefficient of determination (R{sup 2}) over 94. The correlation coefficient (Pearson's, 'r') had a value over 0.95. Both Pb and Pb-210 values had an increasing trend from the bottom ash towards electrostatic precipitator (ESP) ashes. The strong linear correlation between Pb concentrations and Pb-210 activity concentrations gives a credible indication that lead can be measured in ash samples using its radioactive isotope Pb-210. Especially in situations where there are higher concentrations of Pb, for example in the case of wastes from the metallurgic and energy industries, this method could be used to detect the lead concentration quickly and with no chemical processing of the sample. Document available in abstract form only. (authors)

  20. Retrieval of ash properties from IASI measurements (United States)

    Ventress, Lucy J.; McGarragh, Gregory; Carboni, Elisa; Smith, Andrew J.; Grainger, Roy G.


    A new optimal estimation algorithm for the retrieval of volcanic ash properties has been developed for use with the Infrared Atmospheric Sounding Interferometer (IASI). The retrieval method uses the wave number range 680-1200 cm-1, which contains window channels, the CO2 ν2 band (used for the height retrieval), and the O3 ν3 band.Assuming a single infinitely (geometrically) thin ash plume and combining this with the output from the radiative transfer model RTTOV, the retrieval algorithm produces the most probable values for the ash optical depth (AOD), particle effective radius, plume top height, and effective radiating temperature. A comprehensive uncertainty budget is obtained for each pixel. Improvements to the algorithm through the use of different measurement error covariance matrices are explored, comparing the results from a sensitivity study of the retrieval process using covariance matrices trained on either clear-sky or cloudy scenes. The result showed that, due to the smaller variance contained within it, the clear-sky covariance matrix is preferable. However, if the retrieval fails to pass the quality control tests, the cloudy covariance matrix is implemented.The retrieval algorithm is applied to scenes from the Eyjafjallajökull eruption in 2010, and the retrieved parameters are compared to ancillary data sources. The ash optical depth gives a root mean square error (RMSE) difference of 0.46 when compared to retrievals from the MODerate-resolution Imaging Spectroradiometer (MODIS) instrument for all pixels and an improved RMSE of 0.2 for low optical depths (AOD < 0.1). Measurements from the Facility for Airborne Atmospheric Measurements (FAAM) and Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) flight campaigns are used to verify the retrieved particle effective radius, with the retrieved distribution of sizes for the scene showing excellent consistency. Further, the plume top altitudes are compared to derived cloud-top altitudes from the Cloud

  1. Strategy Guideline. Demonstration Home

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, A.; Savage, C.


    This guideline will provide a general overview of the different kinds of demonstration home projects, a basic understanding of the different roles and responsibilities involved in the successful completion of a demonstration home, and an introduction into some of the lessons learned from actual demonstration home projects. Also, this guideline will specifically look at the communication methods employed during demonstration home projects. And lastly, we will focus on how to best create a communication plan for including an energy efficient message in a demonstration home project and carry that message to successful completion.

  2. Strategy Guideline: Demonstration Home

    Energy Technology Data Exchange (ETDEWEB)

    Savage, C.; Hunt, A.


    This guideline will provide a general overview of the different kinds of demonstration home projects, a basic understanding of the different roles and responsibilities involved in the successful completion of a demonstration home, and an introduction into some of the lessons learned from actual demonstration home projects. Also, this guideline will specifically look at the communication methods employed during demonstration home projects. And lastly, we will focus on how to best create a communication plan for including an energy efficient message in a demonstration home project and carry that message to successful completion.

  3. Effect of municipal solid waste incinerator types on characteristics of ashes from different air pollution control devices. (United States)

    Lu, Chien-Hsing; Chuang, Kui-Hao


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

  4. Statistical Analyses of Optimum Partial Replacement of Cement by Fly Ash Based on Complete Consumption of Calcium Hydroxide

    Directory of Open Access Journals (Sweden)

    Ouypornprasert Winai


    Full Text Available The objectives of this technical paper were to propose the optimum partial replacement of cement by fly ash based on the complete consumption of calcium hydroxide from hydration reactions of cement and the long-term strength activity index based on equivalent calcium silicate hydrate as well as the propagation of uncertainty due to randomness inherent in main chemical compositions in cement and fly ash. Firstly the hydration- and pozzolanic reactions as well as stoichiometry were reviewed. Then the optimum partial replacement of cement by fly ash was formulated. After that the propagation of uncertainty due to main chemical compositions in cement and fly ash was discussed and the reliability analyses for applying the suitable replacement were reviewed. Finally an applicability of the concepts mentioned above based on statistical data of materials available was demonstrated. The results from analyses were consistent with the testing results by other researchers. The results of this study provided guidelines of suitable utilization of fly ash for partial replacement of cement. It was interesting to note that these concepts could be extended to optimize partial replacement of cement by other types of pozzolan which were described in the other papers of the authors.

  5. Synthesis and characterization of palm oil fuel ash (POFA) and metakaolin based geopolymer for possible application in nanocoating (United States)

    Khan, Ihsan Ullah; Bhat, A. H.; Masset, Patrick J.; Khan, Farman Ullah; Rehman, Wajid Ur


    The main aim of this study was to synthesize and characterize highly amorphous geopolymer from palm oil fuel ash (POFA) and metakaolin, to be used as nanocoating. Geopolymers are man-made aluminosilicate materials that are amorphous analogues of zeolites. The geopolymers were made by condensing a mixture of raw materials metakaolin and palm oil fuel ash (POFA) with alkaline activator at a fixed ratio at room temperature. The kaolin type clay was calcined at 700 °C for 4hrs to transform it into amorphous metakaolin which is more reactive precursor for geopolymer formation. The characteristics of metakaolin and geopolymers (metakaolin and palm oil fuel ash based geopolymers) were analyzed by using x-ray fluorescence (XRF), Fourier transform infra-red spectrometry (FTIR), Thermogravimetric analysis (TG/DTA) and scanning electron microscopy with energy dispersive x-ray analysis (SEM-EDX). FTIR revealed the presence of Al-O and Si-O stretching vibrations of amorphous alumino-silicate structure for metakaolin, palm oil fuel ash and geopolymers. SEM-EDX images showed the presence of reaction product complementary to NASH (N = Na2O, A = Al2O3, S = SiO2, H = H2O) solid. The resulting geopolymers that were synthesized with NaOH/Na2SiO3 solution cured at 60 °C for 3 days. The results demonstrated the suitability of metakaolin and palm oil fuel ash (POFA) for synthesis of geopolymer at room temperatures.

  6. Characterization of moderate ash-and-gas explosions at Santiaguito volcano, Guatemala, from infrasound waveform inversion and thermal infrared measurements (United States)

    Angelis, S. De; Lamb, O. D.; Lamur, A.; Hornby, A. J.; Aulock, F. W.; Chigna, G.; Lavallée, Y.; Rietbrock, A.


    The rapid discharge of gas and rock fragments during volcanic eruptions generates acoustic infrasound. Here we present results from the inversion of infrasound signals associated with small and moderate gas-and-ash explosions at Santiaguito volcano, Guatemala, to retrieve the time history of mass eruption rate at the vent. Acoustic waveform inversion is complemented by analyses of thermal infrared imagery to constrain the volume and rise dynamics of the eruption plume. Finally, we combine results from the two methods in order to assess the bulk density of the erupted mixture, constrain the timing of the transition from a momentum-driven jet to a buoyant plume, and to evaluate the relative volume fractions of ash and gas during the initial thrust phase. Our results demonstrate that eruptive plumes associated with small-to-moderate size explosions at Santiaguito only carry minor fractions of ash, suggesting that these events may not involve extensive magma fragmentation in the conduit.

  7. Precise gene editing paves the way for derivation of Mannheimia haemolytica leukotoxin-resistant cattle. (United States)

    Shanthalingam, Sudarvili; Tibary, Ahmed; Beever, Jonathan E; Kasinathan, Poothapillai; Brown, Wendy C; Srikumaran, Subramaniam


    Signal peptides of membrane proteins are cleaved by signal peptidase once the nascent proteins reach the endoplasmic reticulum. Previously, we reported that, contrary to the paradigm, the signal peptide of ruminant CD18, the β subunit of β2 integrins, is not cleaved and hence remains intact on mature CD18 molecules expressed on the surface of ruminant leukocytes. Leukotoxin secreted by Mannheimia (Pasteurella) haemolytica binds to the intact signal peptide and causes cytolysis of ruminant leukocytes, resulting in acute inflammation and lung tissue damage. We also demonstrated that site-directed mutagenesis leading to substitution of cleavage-inhibiting glutamine (Q), at amino acid position 5 upstream of the signal peptide cleavage site, with cleavage-inducing glycine (G) results in the cleavage of the signal peptide and abrogation of leukotoxin-induced cytolysis of target cells. In this proof-of-principle study, we used precise gene editing to induce Q(‒5)G substitution in both alleles of CD18 in bovine fetal fibroblast cells. The gene-edited fibroblasts were used for somatic nuclear transfer and cloning to produce a bovine fetus homozygous for the Q(‒5)G substitution. The leukocyte population of this engineered ruminant expressed CD18 without the signal peptide. More importantly, these leukocytes were absolutely resistant to leukotoxin-induced cytolysis. This report demonstrates the feasibility of developing lines of cattle genetically resistant to M. haemolytica-caused pneumonia, which inflicts an economic loss of over $1 billion to the US cattle industry alone.

  8. Latest improvements in microbolometer thin film packaging: paving the way for low-cost consumer applications (United States)

    Yon, J. J.; Dumont, G.; Goudon, V.; Becker, S.; Arnaud, A.; Cortial, S.; Tisse, C. L.


    Silicon-based vacuum packaging is a key enabling technology for achieving affordable uncooled Infrared Focal Plane Arrays (IRFPA) required by a promising mass market that shows momentum for some extensive consumer applications, such as automotive driving assistance, smart presence localization and building management. Among the various approaches studied worldwide, CEA, LETI in partnership with ULIS is committed to the development of a unique technology referred to as PLP (Pixel Level Packaging). In this PLP technology, each bolometer pixel is sealed under vacuum using a transparent thin film deposition on wafer. PLP operates as an array of hermetic micro caps above the focal plane, each enclosing a single microbolometer. In continuation of our on-going studies on PLP for regular QVGA IRFPAs, this paper emphasizes on the innate scalability of the technology which was successfully demonstrated through the development of an 80 × 80 pixel IRFPA. The relevance of the technology with regard to the two formats is discussed, considering both performance and cost issues. We show that the suboptimal fill factor inherent to the PLP arrangement is not so critical when considering smaller arrays preferably fitted for consumer applications. The discussion is supported with the electro-optical performance measurements of the PLP-based 80×80 demonstrator.

  9. Failure to phytosanitize ash firewood infested with emerald ash borer in a small dry kiln using ISPM-15 standards. (United States)

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


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

  10. Screening coal combustion fly ashes for application in geopolymers

    NARCIS (Netherlands)

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


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

  11. Estimating the frequency of volcanic ash clouds over northern Europe (United States)

    Watson, E. J.; Swindles, G. T.; Savov, I. P.; Lawson, I. T.; Connor, C. B.; Wilson, J. A.


    Fine ash produced during explosive volcanic eruptions can be dispersed over a vast area, where it poses a threat to aviation, human health and infrastructure. Here, we focus on northern Europe, which lies in the principal transport direction for volcanic ash from Iceland, one of the most active volcanic regions in the world. We interrogate existing and newly produced geological and written records of past ash fallout over northern Europe in the last 1000 years and estimate the mean return (repose) interval of a volcanic ash cloud over the region to be 44 ± 7 years. We compare tephra records from mainland northern Europe, Great Britain, Ireland and the Faroe Islands, with records of proximal Icelandic volcanism and suggest that an Icelandic eruption with a Volcanic Explosivity Index rating (VEI) ≥ 4 and a silicic magma composition presents the greatest risk of producing volcanic ash that can reach northern Europe. None of the ash clouds in the European record which have a known source eruption are linked to a source eruption with VEI < 4. Our results suggest that ash clouds are more common over northern Europe than previously proposed and indicate the continued threat of ash deposition across northern Europe from eruptions of both Icelandic and North American volcanoes.

  12. Genome sequence and genetic diversity of European ash trees

    DEFF Research Database (Denmark)

    Sollars, Elizabeth S A; Harper, Andrea L; Kelly, Laura J;


    Ash trees (genus Fraxinus, family Oleaceae) are widespread throughout the Northern Hemisphere, but are being devastated in Europe by the fungus Hymenoscyphus fraxineus, causing ash dieback, and in North America by the herbivorous beetle Agrilus planipennis. Here we sequence the genome of a low...... to an emerging health threat in a non-model organism opens the way for mitigation of the epidemic....

  13. Leaching of nutrient salts from fly ash from biomass combustion

    DEFF Research Database (Denmark)

    Thomsen, Kaj; Vu, Duc Thuong; Stenby, Mette;


    . The first method was a counter current moving bed process in four stages. The ash was kept in filter bags and leached with water that was introduced into the bags at 40-50°C. In the second method, fly ash and water was brought into contact in a partially fluidized bed. The third method was a counter current...

  14. A fly ash and shale fired brick production line

    Institute of Scientific and Technical Information of China (English)



    The article describes the fly ash and shale fired brick production line with annual output of 1250 million bricks, designed by Xi'an Research and Design Institute of Wall and Roof Material, commissioned by QinDian Building Material Subcompany, and set an example for using fly ash and shale in China.

  15. 'Crazy-Paving' Patterns on High-Resolution CT Scans in Patients with Pulmonary Complications after Hematopoietic Stem Cell Transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Marchiori, Edson; Escuissato, Dante L.; Gasparetto, Taisa Davaus; Considera, Daniela Peixoto [Federal University, Sao Paulo (Brazil); Franquet, Tomas [Hospital de Sant Pau, Universitat Autonoma de Barcelona, Barcelona (Spain)


    To describe the pulmonary complications following hematopoietic stem cell transplantation (HSCT) that can present with a 'crazy-paving' pattern in high-resolution CT scans. Retrospective review of medical records from 2,537 patients who underwent HSCT. The 'crazy-paving' pattern consists of interlobular and intralobular septal thickening superimposed on an area of ground-glass attenuation on high-resolution CT scans. The CT scans were retrospectively reviewed by two radiologists, who reached final decisions by consensus. We identified 10 cases (2.02%), seven male and three female, with pulmonary complications following HSCT that presented with the 'crazy-paving' pattern. Seven (70%) patients had infectious pneumonia (adenovirus, herpes simplex, influenza virus, cytomegalovirus, respiratory syncytial virus, and toxoplasmosis), and three patients presented with non-infectious complications (idiopathic pneumonia syndrome and acute pulmonary edema). The 'crazy-paving' pattern was bilateral in all cases, with diffuse distribution in nine patients (90%), predominantly in the middle and inferior lung regions in seven patients (70%), and involving the anterior and posterior regions of the lungs in nine patients (90%). The 'crazy-paving' pattern is rare in HSCT recipients with pulmonary complications and is associated with infectious complications more commonly than non-infectious conditions.

  16. Cadmium in insects after ash fertilization

    Institute of Scientific and Technical Information of China (English)

    Martin Lodenius; Jussi Josefsson; Kari Heli(o)vaara; Esa Tulisalo; Matti Nummelin


    Ash fertilization of forests returns nutrients to forest ecosystems and has a positive effect on soil pH.but it also may elevate Cd concentrations of forest biota.Cadmium concentrations of some forest insects(Formica ants.carabids and Coleopteran larvac from decaying wood)were investigated in southern Finland where two plots were fertilized with wood ash,while two other plots represented anfertilized control plots.In ants,mean Cd concentration was 3.6±1.4 mg/kg.with nest workers having significantly higher concen-trations than workers trapped in pitfall traps.Concentrations at fertilized and unfertilized plots were similar.In carabid beetles,the average Cd concentration of Carabus glabratus was 0.44±0.36 mg/kg.with no significant difference between control plots and fertilized plots.In another carabid beetle,Pterostichus niger,mean Cd concentration was higher at fertilized plots compared to control plots.We conclude that the variation of Cd concentra-tions in the insects studied is more efficiently controlled by species-specific differences than fertilization history of the forest floor.

  17. Mesoporous Silica from Rice Husk Ash

    Directory of Open Access Journals (Sweden)

    V.R. Shelke


    Full Text Available Mesoporous silica is used as a raw material in several areas: in preparation of catalysts, in inks, as a concrete hardening accelerator, as a component of detergents and soaps, as a refractory constituent etc. Sodium silicate is produced by reacting rice hull ash (RHA with aqueous NaOH and silica is precipitated from the sodium silicate by acidification. In the present work, conversion of about 90% of silica contained in RHA into sodium silicate was achieved in an open system at temperatures of about 100 °C. The results showed that silica obtained from RHA is mesoporous, has a large surface area and small particle size. Rice Husk is usually mixed with coal and this mixture is used for firing boilers. The RHA therefore, usually contains carbon particles. Activated carbon embedded on silica has been prepared using the carbon already present in RHA. This carbon shows good adsorption capacity. ©2010 BCREC UNDIP. All rights reserved(Received: 25th April 2010, Revised: 17th June 2010, Accepted: 24th June 2010[How to Cite: V.R. Shelke, S.S. Bhagade, S.A. Mandavgane. (2010. Mesoporous Silica from Rice Husk Ash. Bulletin of Chemical Reaction Engineering and Catalysis, 5 (2: 63-67. doi:10.9767/bcrec.5.2.793.63-67][DOI:

  18. Radioactive wastes dispersed in stabilized ash cements

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, J.B.; Taylor, C.M.V.; Sivils, L.D.; Carey, J.W.


    One of the most widely-used methods for the solidification/stabilization of low-level radwaste is by incorporation into Type-I/II ordinary portland cement (OPC). Treating of OPC with supercritical fluid carbon dioxide (SCCO{sub 2}) has been shown to significantly increase the density, while simultaneously decreasing porosity. In addition, the process significantly reduces the hydrogenous content, reducing the likelihood of radiolytic decomposition reactions. This, in turn, permits increased actinide loadings with a concomitant reduction in disposable waste volume. In this article, the authors discuss the combined use of fly-ash-modified OPC and its treatment with SCCO{sub 2} to further enhance immobilization properties. They begin with a brief summary of current cement immobilization technology in order to delineate the areas of concern. Next, supercritical fluids are described, as they relate to these areas of concern. In the subsequent section, they present an outline of results on the application of SCCO{sub 2} to OPC, and its effectiveness in addressing these problem areas. Lastly, in the final section, they proffer their thoughts on why they believe, based on the OPC results, that the incorporation of fly ash into OPC, followed by supercritical fluid treatment, can produce highly efficient wasteforms.

  19. Hot-Gas Filter Ash Characterization Project

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, M.L.; Hurley, J.P.; Dockter, B.A.; O`Keefe, C.A.


    Large-scale hot-gas filter testing over the past 10 years has revealed numerous cases of cake buildup on filter elements that has been difficult, if not impossible, to remove. At times, the cake can blind or bridge between candle filters, leading to filter failure. Physical factors, including particle-size distribution, particle shape, the aerodynamics of deposition, and system temperature, contribute to the difficulty in removing the cake, but chemical factors such as surface composition and gas-solid reactions also play roles in helping to bond the ash to the filters or to itself. This project is designed to perform the research necessary to determine the fuel-, sorbent-, and operations-related conditions that lead to blinding or bridging of hot-gas particle filters. The objectives of the project are threefold: (1) Determine the mechanisms by which a difficult-to-clean ash is formed and how it bridges hot-gas filters (2) Develop a method to determine the rate of bridging based on analyses of the feed coal and sorbent, filter properties, and system operating conditions and (3) Suggest and test ways to prevent filter bridging.

  20. Phosphorus Recovery from Ashes of Sewage Sludge

    Energy Technology Data Exchange (ETDEWEB)

    Cornel, Peter; Schaum, Peter


    About 90% of the incoming phosphorus load of waste water is eliminated by waste water treatment and transferred into the sewage sludge. Considerable amounts of sewage sludge can not be used agriculturally but are incinerated. Thus the ash from mono sludge incineration plants contains significant amounts of phosphorus (up to 25% P{sub 2}O{sub 5}) and could be used as raw material in fertilizer industry. The ash is hygienically harmless and free of organic substances. The ratio of phosphorus to heavy metals is basically the same as in the sewage sludge. The first step in separating phosphorus from heavy metals is to dissolve phosphorus by extraction. The most promising way seems to be the release of phosphorus with acids or bases. With 1 m sulphuric acid it is possible to release phosphorus completely. By use of acid most of the heavy metals dissolve, too. With caustic soda as solvent, only 30-40% of the phosphorus can be dissolved but the eluate is almost free of heavy metals. The amount of phosphorus which can be released with caustic soda, depends on the applied precipitant (Al or Fe salts) for phosphorus elimination at the waste water treatment. (author)

  1. ASH position paper: hypertension in pregnancy. (United States)

    Lindheimer, Marshall D; Taler, Sandra J; Cunningham, F Gary


    The American Society of Hypertension is publishing a series of Position Papers in their official journals throughout the 2008-2009 years. The following Position Paper originally appeared: JASH. 2008;2(6):484-494. Hypertension complicates 5% to 7% of all pregnancies. A subset of preeclampsia, characterized by new-onset hypertension, proteinuria, and multisystem involvement, is responsible for substantial maternal and fetal morbidity and is a marker for future cardiac and metabolic disease. This American Society of Hypertension, Inc (ASH) position paper summarizes the clinical spectrum of hypertension in pregnancy, focusing on preeclampsia. Recent research breakthroughs relating to etiology are briefly reviewed. Topics include classification of the different forms of hypertension during pregnancy, status of the tests available to predict preeclampsia, and strategies to prevent preeclampsia and to manage this serious disease. The use of antihypertensive drugs in pregnancy, and the prevention and treatment of the convulsive phase of preeclampsia, eclampsia, with intravenous magnesium sulfate is also highlighted. Of special note, this guideline article, specifically requested, reviewed, and accepted by ASH, includes solicited review advice from the American College of Obstetricians and Gynecologists.

  2. Fire severity effects on ash extractable Total Phosphorous (United States)

    Pereira, Paulo; Úbeda, Xavier; Martin, Deborah


    Phosphorous (P) is a crucial element to plant nutrition and limits vegetal production. The amounts of P in soil are lower and great part of this nutrient is absorbed or precipitated. It is well known that fire has important implications on P cycle, that can be lost throughout volatilization, evacuated with the smoke, but also more available to transport after organic matter mineralization imposed by the fire. The release of P depends on ash pH and their chemical and physical characteristics. Fire temperatures impose different severities, according to the specie affected and contact time. Fire severity is often evaluated by ash colour and this is a low-cost and excellent methodology to assess the fire effects on ecosystems. The aim of this work is study the ash properties physical and chemical properties on ash extractable Total Phosphorous (TP), collected in three wildfires, occured in Portugal, (named, (1) Quinta do Conde, (2) Quinta da Areia and (3) Casal do Sapo) composed mainly by Quercus suber and Pinus pinaster trees. The ash colour was assessed using the Munsell color chart. From all three plots we analyzed a total of 102 ash samples and we identified 5 different ash colours, ordered in an increasing order of severity, Very Dark Brown, Black, Dark Grey, Very Dark Grey and Light Grey. In order to observe significant differences between extractable TP and ash colours, we applied an ANOVA One Way test, and considered the differences significant at a p<0.05. The results showed that significant differences in the extractable TP among the different ash colours. Hence, to identify specific differences between each ash colour, we applied a post-hoc Fisher LSD test, significant at a p<0.05. The results obtained showed significant differences between the extractable TP from Very dark Brown and Black ash, produced at lower severities, in relation to Dark Grey, Very Dark Grey and Light Grey ash, generated at higher severities. The means of the first group were higher

  3. Manufacturing Demonstration Facility (MDF) (United States)

    Federal Laboratory Consortium — The U.S. Department of Energy Manufacturing Demonstration Facility (MDF) at Oak Ridge National Laboratory (ORNL) provides a collaborative, shared infrastructure to...

  4. Electrical charging of ash in Icelandic volcanic plumes

    CERN Document Server

    Aplin, Karen L; Nicoll, Keri A


    The existence of volcanic lightning and alteration of the atmospheric potential gradient in the vicinity of near-vent volcanic plumes provides strong evidence for the charging of volcanic ash. More subtle electrical effects are also visible in balloon soundings of distal volcanic plumes. Near the vent, some proposed charging mechanisms are fractoemission, triboelectrification, and the so-called "dirty thunderstorm" mechanism, which is where ash and convective clouds interact electrically to enhance charging. Distant from the vent, a self-charging mechanism, probably triboelectrification, has been suggested to explain the sustained low levels of charge observed on a distal plume. Recent research by Houghton et al. (2013) linked the self-charging of volcanic ash to the properties of the particle size distribution, observing that a highly polydisperse ash distribution would charge more effectively than a monodisperse one. Natural radioactivity in some volcanic ash could also contribute to self-charging of volcan...


    Energy Technology Data Exchange (ETDEWEB)

    Robert Hurt; Eric Suuberg; John Veranth; Xu Chen


    The overall objective of the present project is to identify and assess strategies and solutions for the management of industry problems related to carbon in ash. Specific research issues to be addressed include: (1) the effect of parent fuel selection on ash properties and adsorptivity, including a first ever examination of the air entrainment behavior of ashes from alternative (non-coal) fuels; (2) the effect of various low-NOx firing modes on ash properties and adsorptivity; and (3) the kinetics and mechanism of ash ozonation. This data will provide scientific and engineering support of the ongoing process development activities. During this fourth project period we completed the characterization of ozone-treated carbon surfaces and wrote a comprehensive report on the mechanism through which ozone suppresses the adsorption of concrete surfactants.

  6. Self-healing ability of fly ash-cement systems

    Energy Technology Data Exchange (ETDEWEB)

    Pipat Termkhajornkit; Toyoharu Nawa; Yoichi Yamashiro; Toshiki Saito [Lafarge Research Centre, Quentin Fallavier (France). Reactive Components Department


    Concrete is susceptible to cracking due to both autogenous and drying shrinkage. Nevertheless, most of these types of cracks occur before 28 days. Because fly ash continues to hydrate after 28 days, it is likely that hydrated products from fly ash may modify microstructure, seal these cracks, and prolong the service life. This research investigates the self-healing ability of fly ash-cement paste. Compressive strength, porosity, chloride diffusion coefficients, hydration reactions and hydrated products were studied. The research focuses on behavior after 28 days. According to the experimental results, the fly ash-cement system has the self-healing ability for cracks that occur from shrinkage. The self-healing ability increased when the fraction of fly ash increased.

  7. Activated blended cement containing high volume coal fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Shi, C.J.; Qian, J.S. [CJS Technology Inc., Burlington, ON (Canada)


    This study investigated the strength and equilibrium water extraction of blended cement containing high volume coal fly ash and activator CaCl{sub 2}. The addition of CaCl{sub 2} increased the strength of cement very significantly. Equilibrium water extraction indicated that the addition of CaCl{sub 2} decreased the pH of the pore solution, but accelerated the pozzolanic reactions between coal fly ash and lime, which became more obvious when the volume of fly ash in the cement was increased from 50-70%. Results from both strength and water extraction testing could conclude that CaCl{sub 2} is a good activator for the activation of pozzolanic reactivity of fly ash and for the improvement of early properties of fly ash cement and concrete.

  8. Synthesis and characterization of fly ash-zinc oxide nanocomposite

    Directory of Open Access Journals (Sweden)

    Kunal Yeole


    Full Text Available Fly ash, generated in thermal power plants, is recognized as an environmental pollutant. Thus, measures are required to be undertaken to dispose it in an environmentally friendly method. In this paper an attempt is made to coat zinc oxide nano-particles on the surface of fly ash by a simple and environmentally friendly facile chemical method, at room temperature. Zinc oxide may serve as effective corrosion inhibitor by providing sacrificial protection. Concentration of fly ash was varied as 5, 10 and 15 (w/w % of zinc oxide. It was found that crystallinity increased, whereas particle size, specific gravity and oil absorption value decreased with increased concentration of fly ash in zinc oxide, which is attributed to the uniform distribution of zinc oxide on the surface of fly ash. These nanocomposites can potentially be used in commercial applications as additive for anticorrosion coatings.

  9. Dry coal fly ash cleaning using rotary triboelectrostatic separator

    Institute of Scientific and Technical Information of China (English)

    TAO Daniel; FAN Mao-ming; JIANG Xin-kai


    More than 80 million metric tons of fly ash is produced annually in the U.S. As coal combustion by-product. Coal fly ash can be converted to value-added products if unburned carbon is reduced to less than 2.5%. However, most of fly ash is currently landfilled as waste due to lack of efficient purification technologies to separate unburned carbon from fly ash. A rotary triboelectrostatic separator has been developed and patented recently at the University of Kentucky with unique features. Several fly ash samples have been used to understand the effects of major process parameters on the separation performance. The results show that compared to existing triboelectrostatic separators, the rotary triboelectrostatic separator has significant advantages in particle charging efficiency, solids throughput, separation efficiency, applicable particle size range.

  10. Use of Recycled Aggregate and Fly Ash in Concrete Pavement

    Directory of Open Access Journals (Sweden)

    Myle N. James


    Full Text Available Problem statement: Recycled materials aggregate from the demolished concrete structures and fly ash from burning coal shows the possible application as structural and non structural components in concrete structures. This research aims to evaluate the feasibility of using concrete containing recycled concrete aggregate and fly ash in concrete pavement. Approach: Two water cement ratio (0.45 and 0.55 the compressive strength, modulus of electricity and flexural strength for concrete with recycled aggregate and fly ash with 0, 25% replacing cement in mass were considered. Results: The material properties of recycled aggregate concrete with fly ash indicate comparable results with that of concrete with natural aggregate and without fly ash. Conclusion/Recommendations: The recycled materials could be used in concrete pavement and it will promote the sustainability of concrete.

  11. Low temperature magnetic characterisation of fire ash residues (United States)

    Peters, C.; Thompson, R.; Harrison, A.; Church, M. J.

    Fire ash is ideally suited to mineral magnetic studies. Both modern (generated by controlled burning experiments) and archaeological ash deposits have been studied, with the aim of identifying and quantifying fuel types used in prehistory. Low temperature magnetic measurements were carried out on the ash samples using an MPMS 2 SQUID magnetometer. The low temperature thermo-remanence cooling curves of the modern ash display differences between fuel sources. Wood and well-humified peat ash display an increase in remanence with cooling probably related to a high superparamagnetic component, consistent with room temperature frequency dependent susceptibilities of over 7%. In comparison fibrous-upper peat and peat turf display an unusual decrease in remanence, possibly due to an isotropic point of grains larger than superparamagnetic in size. The differences have been successfully utilised in unmixing calculations to quantify fuel components within four archaeological deposits from the Northern and Western Isles of Scotland.

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


    Franus, Wojciech; Wdowin, Magdalena; Franus, Małgorzata


    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...

  13. Analysis list: ash-2 [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ash-2 Adult,Embryo + ce10,, ...


    Energy Technology Data Exchange (ETDEWEB)

    Robert Hurt; Eric Suuberg; John Veranth; Xu Chen


    The overall objective of the present project is to identify and assess strategies and solutions for the management of industry problems related to carbon in ash. Specific research issues to be addressed include: (1) the effect of parent fuel selection on ash properties and adsorptivity, including a first ever examination of the air entrainment behavior of ashes from alternative (non-coal) fuels; (2) the effect of various low-NOx firing modes on ash properties and adsorptivity; and (3) the kinetics and mechanism of ash ozonation. This data will provide scientific and engineering support of the ongoing process development activities. During this fourth project period we completed the characterization of ozone-treated carbon surfaces and wrote a comprehensive report on the mechanism through which ozone suppresses the adsorption of concrete surfactants.

  15. Application of Fly Ash from Solid Fuel Combustion in Concrete

    DEFF Research Database (Denmark)

    Pedersen, Kim Hougaard


    reactor to test the impact of changes in operating conditions and fuel type on the AEA adsorption of ash and NOx formation. Increased oxidizing conditions, obtained by improved fuel-air mixing or higher excess air, decreased the AEA requirements of the produced ash by up to a factor of 25. This was due...... on a carbon black. The reactor was modeled with CFD and a relationship between oxygen concentration in the early stage of combustion and the AEA adsorption properties of the ash was observed. The NOx formation increased by up to three times with more oxidizing conditions and thus, there was a trade....... The AEA requirements of a fly ash can be suppressed by exposing it to oxidizing species, which oxidizes the carbon surface and thus prevents the AEA to be adsorbed. In the present work, two fly ashes have been ozonated in a fixed bed reactor and the results showed that ozonation is a potential post...

  16. Analysis of Content of Selected Critical Elements in Fly Ash

    Directory of Open Access Journals (Sweden)

    Makowska Dorota


    Full Text Available Pursuant to the new mineral policy of the European Union, searching for new sources of raw materials is required. Coal fly ash has long been considered as a potential source of a number of critical elements. Therefore, it is important to monitor the contents of the critical elements in fly ash from coal combustion. The paper presents the results of examinations of the contents of selected elements, i.e. beryllium, cobalt, chromium and germanium in fly ash from Polish power plants. The results of the conducted investigations indicate that the examined ash samples from bituminous coal combustion cannot be treated as a potential source of the analysed critical elements. The content of these elements in ash, though slightly higher than their average content in the sedimentary rocks, is, however, not high enough to make their recovery technologically and economically justified at this moment.

  17. Experimental measurements of the thermal conductivity of ash deposits: Part 1. Measurement technique

    Energy Technology Data Exchange (ETDEWEB)

    A. L. Robinson; S. G. Buckley; N. Yang; L. L. Baxter


    This paper describes a technique developed to make in situ, time-resolved measurements of the effective thermal conductivity of ash deposits formed under conditions that closely replicate those found in the convective pass of a commercial boiler. Since ash deposit thermal conductivity is thought to be strongly dependent on deposit microstructure, the technique is designed to minimize the disturbance of the natural deposit microstructure. Traditional techniques for measuring deposit thermal conductivity generally do not preserve the sample microstructure. Experiments are described that demonstrate the technique, quantify experimental uncertainty, and determine the thermal conductivity of highly porous, unsintered deposits. The average measured conductivity of loose, unsintered deposits is 0.14 {+-} 0.03 W/(m K), approximately midway between rational theoretical limits for deposit thermal conductivity.

  18. Summary of the program 'Environmentally correct utilization of ashes' at Vaermeforsk 2002-2005; Syntes av delprogrammet 'Miljoeriktig anvaendning av askor' foer 2002-2005

    Energy Technology Data Exchange (ETDEWEB)

    Bjurstroem, Henrik [AaF-Process AB, Stockholm (Sweden)


    has been thought to be. However, highly soluble salts may be a cause for restrictions. Although one should interpret results from calculations with cautiousness it seems that dust from the roads settling on vegetables grown in the vicinity of a road is a larger problem. The tests used today to determine the geotechnical properties of materials aim primarily at checking if these are within specifications. As for other recovered materials, somewhat different tests must be used to ascertain that ashes can be used to provide a function. Three bottom ashes were investigated, and the results confirmed that the tests proposed are relevant. Some of the tests need to be refined. The properties related to moisture may become critical, in particular frost-heave in moist ashes. Work has been concluded with a handbook containing guidelines for building unpaved roads using fly ashes. The standards in force today on the use of ashes in cement and concrete refer to the utilization of coal ashes rich in silica. The Swedish ashes from biofuels do not fit into these standards. Their use as fine filler in concrete has been developed and demonstrated. Fly ash has been shown to be a replacement for cement in mines. The main thrust in the Ash Programme for landfills is on covers using ash and sludge from municipal wastewater treatment. Ashes provide the cover layer a high pH value that hinders biological degradation of the sludge as well as mechanical stability. Projects have investigated mixing proportions between ash and digested sludge and prepared in all four pilot surfaces on landfills, with satisfactory results. These projects have been complemented with an investigation of the chemical stability of the digested sludge. Mine tailings have been studied in two projects: In the first project digested sludge is used as support for vegetation on the mounds. The second role filled by the sludge is to prevent oxygen from reaching the sulphides tailings. To prevent roots from the vegetation

  19. Kinetics and Catalysis Demonstrations. (United States)

    Falconer, John L.; Britten, Jerald A.


    Eleven videotaped kinetics and catalysis demonstrations are described. Demonstrations include the clock reaction, oscillating reaction, hydrogen oxidation in air, hydrogen-oxygen explosion, acid-base properties of solids, high- and low-temperature zeolite reactivity, copper catalysis of ammonia oxidation and sodium peroxide decomposition, ammonia…

  20. Toy Demonstrator's "VISIT" Handbook. (United States)

    Levenstein, Phyllis

    The role of the toy demonstrator in a home-based, mother-involved intervention effort (Verbal Interaction Project) is presented in this handbook for staff members. It is believed that the prerequisites for functioning in the toy demonstrator's role are a sense of responsibility, patience with the children and their mothers, and willingness to be…

  1. Better Ira Remsen Demonstration (United States)

    Dalby, David K.; Maynard, James H.; Moore, John W.


    Many versions of the classic Ira Remsen experience involving copper and concentrated nitric acid have been used as lecture demonstrations. Remsen's original reminiscence from 150 years ago is included in the Supporting Information, and his biography can be found on the Internet. This article presents a new version that makes the demonstration more…

  2. Levitation Kits Demonstrate Superconductivity. (United States)

    Worthy, Ward


    Describes the "Project 1-2-3" levitation kit used to demonstrate superconductivity. Summarizes the materials included in the kit. Discusses the effect demonstrated and gives details on how to obtain kits. Gives an overview of the documentation that is included. (CW)

  3. Feasibility study on solidification of municipal solid waste incinerator fly ash with circulating fluidized bed combustion coal fly ash. (United States)

    Liu, Wenshi; Hou, Haobo; Zhang, Chuhao; Zhang, Dajie


    The objective of this study was to assess the feasibility of solidification of municipal solid waste incinerator (MSWI) fly ash with circulation fluidized bed combustion (CFBC) fly ash, which is unsuitable as a cement replacement due to its high amounts of carbon, lime and anhydrite. The solidification process was conducted on samples prepared from MSWI fly ash, binders (cement clinkers and CFBC fly ash were mixed at two replacement ratios) and water (water/solid weight ratio = 0.4), among which the MSWI fly ash replaced each binder at the ratio of 0, 20, 40, 60 and 80% by dry weight. The samples were subjected to compressive strength tests and Toxicity Characteristic Leaching Procedure and the results showed that all solidified MSWI fly ash can meet the landfill standard imposed by US EPA after 28 days of curing. Micro-analysis (X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectrophotometry) revealed that the main hydrate products were C-S-H gel and ettringite, which have a positive effect on heavy metals retention. Therefore, this method provides a possibility to achieve a cheap and effective solution for MSWI fly ash management and use for CFBC fly ash.

  4. Fluidization characteristics of power-plant fly ashes and fly ash-charcoal mixtures. [MS Thesis; 40 references

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, C.T.


    As a part of the continuing research on aluminum recovery from fly ash by HiChlor process, a plexiglass fluidization column system was constructed for measurement of fluidization parameters for power-plant fly ashes and fly ash-charcoal mixtures. Several bituminous and subbituminous coal fly ashes were tested and large differences in fluidization characteristics were observed. Fly ashes which were mechanically collected fluidized uniformly at low gas flow rates. Most fly ashes which were electrostatically precipitated exhibited channeling tendency and did not fluidize uniformly. Fluidization characteristics of electrostatically collected ashes improve when the finely divided charcoal powder is added to the mixture. The fluidization of the mixture was aided initially by a mechanical stirrer. Once the fluidization had succeeded, the beds were ready to fluidize without the assistance of a mechanical action. Smooth fluidization and large bed expansion were usually observed. The effects of charcoal size and aspect ratio on fluidization characteristics of the mixtures were also investigated. Fluidization characteristics of a fly ash-coal mixture were tested. The mixture fluidized only after being oven-dried for a few days.

  5. Effects of the emerald ash borer invasion on the community composition of arthropods associated with ash tree boles (United States)

    Emerald ash borer (EAB), Agrilus planipennis Fairmaire is an invasive non-native wood-boring beetle that has killed hundreds of millions of ash trees (Fraxinus spp.) in North America, and threatens to extirpate the ecological services provided by the genus. Identifying the arthropod community assoc...

  6. Stem cell-paved biobridges facilitate stem transplant and host brain cell interactions for stroke therapy. (United States)

    Duncan, Kelsey; Gonzales-Portillo, Gabriel S; Acosta, Sandra A; Kaneko, Yuji; Borlongan, Cesar V; Tajiri, Naoki


    Distinguished by an infarct core encased within a penumbra, stroke remains a primary source of mortality within the United States. While our scientific knowledge regarding the pathology of stroke continues to improve, clinical treatment options for patients suffering from stroke are extremely limited. Tissue plasminogen activator (tPA) remains the sole FDA-approved drug proven to be helpful following stroke. However, due to the need to administer the drug within 4.5h of stroke onset its usefulness is constrained to less than 5% of all patients suffering from ischemic stroke. One experimental therapy for the treatment of stroke involves the utilization of stem cells. Stem cell transplantation has been linked to therapeutic benefit by means of cell replacement and release of growth factors; however the precise means by which this is accomplished has not yet been clearly delineated. Using a traumatic brain injury model, we recently demonstrated the ability of transplanted mesenchymal stromal cells (MSCs) to form a biobridge connecting the area of injury to the neurogenic niche within the brain. We hypothesize that MSCs may also have the capacity to create a similar biobridge following stroke; thereby forming a conduit between the neurogenic niche and the stroke core and peri-infarct area. We propose that this biobridge could assist and promote interaction of host brain cells with transplanted stem cells and offer more opportunities to enhance the effectiveness of stem cell therapy in stroke. This article is part of a Special Issue entitled SI: Cell Interactions In Stroke.

  7. Behavioral responses in structured populations pave the way to group optimality. (United States)

    Akçay, Erol; Van Cleve, Jeremy


    An unresolved controversy regarding social behaviors is exemplified when natural selection might lead to behaviors that maximize fitness at the social-group level but are costly at the individual level. Except for the special case of groups of clones, we do not have a general understanding of how and when group-optimal behaviors evolve, especially when the behaviors in question are flexible. To address this question, we develop a general model that integrates behavioral plasticity in social interactions with the action of natural selection in structured populations. We find that group-optimal behaviors can evolve, even without clonal groups, if individuals exhibit appropriate behavioral responses to each other's actions. The evolution of such behavioral responses, in turn, is predicated on the nature of the proximate behavioral mechanisms. We model a particular class of proximate mechanisms, prosocial preferences, and find that such preferences evolve to sustain maximum group benefit under certain levels of relatedness and certain ecological conditions. Thus, our model demonstrates the fundamental interplay between behavioral responses and relatedness in determining the course of social evolution. We also highlight the crucial role of proximate mechanisms such as prosocial preferences in the evolution of behavioral responses and in facilitating evolutionary transitions in individuality.

  8. Direct Determination of Ascorbic Acid in a Grapefruit: Paving the Way for In Vivo Spectroelectrochemistry. (United States)

    Garoz-Ruiz, Jesus; Heras, Aranzazu; Colina, Alvaro


    The study of real samples is more complicated than the study of other systems. However, the inherent advantages of UV-vis absorption spectroelectrochemistry should overcome some difficulties related to direct measurements in complex matrices. For this reason, a singular spectroelectrochemistry device has been fabricated and validated. The novel cell is based on single-walled carbon nanotubes, which are filtered and subsequently press-transferred on a polyethylene terephthalate support using a stencil with a custom design. With this new methodology, working, counter, and reference electrodes are completely flat on the surface, where two optical fibers are fixed in a long optical path length configuration. To demonstrate the usefulness of this device and the power of spectroelectrochemistry techniques to solve problems of the current world, this device is used to quantitatively detect the concentration of ascorbic acid in a complex matrix such as a fruit, directly, without any previous sample pretreatment. The ease to fabricate the device, the advantages related to its use, and the excellent results obtained not only with univariate but also with multivariate analysis, shed more light on the analysis of samples as they occur in nature. According to the particular features of this cell, to the best of our knowledge this is the first spectroelectrochemical sensor that can be inserted directly in a biological matrix, laying the groundwork to perform in vivo measurements in a near future.

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  10. Wildfire Ash: Chemical Composition, Ash-Soil Interactions and Environmental Impacts (United States)

    Brook, Anna; Hamzi, Seham; Wittenberg, Lea


    Of the five classical factors of soil formation, climate, parent material, topography, time, organisms, and recently recognized human activity, it is the latter factor which discretely includes fire and post-burn impact. However, it is considered that soil undergoing fire just experience a temporary removal of the top organic horizon, thus slightly modified and often labeled as 'temporarily disturbed' soil or soil 'under restoration/rehabilitation'. In fact the suggested seventh factor, post-burned produced ash, can act both dependently and independently of the other soil forming factors (Levin et al., 2013; Certini 2013). They are interdependent in cases where ash influences occur on time scales similar to 'natural' soil formation (Keesstra et ai., 2014) such as changes in vegetation. On the other hand, in post-fire areas a strong dependency is expected between soil-water retention mechanism, climate and topography. Wild-land fires exert many changes on the physical, chemical, mineralogical, biological, and morphological properties of soil that, in turn, affect the soil's hydrology and nutrient flux, modifying its ability to support vegetation and resist erosion. The ash produced by forest fires is a complex mixture composed of organic and inorganic particles characterized by vary physical-chemical and morphological properties. The importance of this study is straightforwardly related to the frequency and large-scales wildfires in Mediterranean region. In fact, wildfires are major environmental and land management concern in the world, where the number and severity of wildfires has increased during the past decades (Bodi, 2013). Certini (2013) assumed that cumulatively all of the vegetated land is burned in about 31 years annually affecting 330-430 Mha (over 3% of the Earth's surface) and wide range of land cover types worldwide including forests, peatlands, shrublands and grasslands. Whereas, the fire is identified as an important factor in soil formation, the

  11. Fibrous Fillers to Manufacture Ultra High Ash/Performance Paper

    Energy Technology Data Exchange (ETDEWEB)

    Dr. VIjay K. Mathur


    The paper industry is one of the largest users of energy and emitters of CO2 in the US manufacturing industry. In addition to that, it is facing tremendous financial pressure due to lower cost imports. The fine paper industry has shrunk from 15 million tons per year production to 10 million tons per year in the last 5 years. This has resulted in mill closures and job loses. The AF&PA and the DOE formed a program called Agenda 2020 to help in funding to develop breakthrough technologies to provide help in meeting these challenges. The objectives of this project were to optimize and scale-up Fibrous Fillers technology, ready for commercial deployment and to develop ultra high ash/high performance paper using Fibrous Fillers. The goal was to reduce energy consumption, carbon footprint, and cost of manufacturing paper and related industries. GRI International (GRI) has been able to demonstrate the techno - economic feasibility and economic advantages of using its various products in both handsheets as well as in commercial paper mills. GRI has also been able to develop sophisticated models that demonstrate the effect of combinations of GRI's fillers at multiple filler levels. GRI has also been able to develop, optimize, and successfully scale-up new products for use in commercial paper mills.

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  13. Effect of particle volume fraction on the settling velocity of volcanic ash particles: implications for ash dispersion models (United States)

    Del Bello, E.; Taddeucci, J.; De'Michieli Vitturi, M.; Scarlato, P.; Andronico, D.; Scollo, S.; Kueppers, U.


    We present the first report of experimental measurements of the enhanced settling velocity of volcanic particles as function of particle volume fraction. In order to investigate the differences in the aerodynamic behavior of ash particles when settling individually or in mass, we performed systematic large-scale ash settling experiments using natural basaltic and phonolitic ash. By releasing ash particles at different, controlled volumetric flow rates, in an unconstrained open space and at minimal air movement, we measured their terminal velocity, size, and particle volume fraction with a high-speed camera at 2000 fps. Enhanced settling velocities of individual particles increase with increasing particle volume fraction. This suggests that particle clustering during fallout may be one reason explaining larger than theoretical depletion rates of fine particles from volcanic ash clouds. We provide a quantitative empirical model that allows to calculate, from a given particle size and density, the enhanced velocity resulting from a given particle volume fraction. The proposed model has the potential to serve as a simple tool for the prediction of the terminal velocity of ash of an hypothetical distribution of ash of known particle size and volume fraction. This is of particular importance for advection-diffusion transport model of ash where generally a one-way coupling is adopted, considering only the flow effects on particles. To better quantify the importance of the enhanced settling velocity in ash dispersal, we finally introduced the new formulation in a Lagrangian model calculating for realistic eruptive conditions the resulting ash concentration in the atmosphere and on the ground.

  14. Estimation of ash recirculation effect upon ash collector efficiency by the example of a TsBR-150U-1280 multicyclone collector (United States)

    Elsukov, V. K.; Latushkina, S. V.


    Problems of the mathematical estimation of the amount of recirculating ash and its effect upon the efficiency of gas treating within ash collectors with the scroll and semiscroll gas supply, which are equipped by a gas and ash recirculation system, are considered. Based on the analysis of various publications and operational experience, a conclusion is drawn regarding the complex and substantial effect of the recirculation system upon the ash collector efficiency. The following research tasks are posed: computational determination of ash weight at the ash collector inlet subject to its recirculation, development of measures for enhancement of the ash collector, and estimation of these measures. A computation procedure for consumption of recirculating ash in the ash collector and its sections with the use of formulas of the geometrical progression is represented. Based on the represented procedure as applied to a TsBR-150U-1280 multicyclone collector collecting ash of coal of an Irsha-Borodinsk coalfield, corresponding ash consumptions are determined, including that at which the effective operation of the ash collector is provided. Various variants of the modernization of the mentioned multicyclone collector are developed and estimated. Conclusions are drawn regarding the necessity for further investigations for improvement of the represented procedure, in particular, the effect of the gas speed (boiler load) upon the efficiency of various ash collector units, recirculating ash consumption, and clogging their cyclone units.

  15. Binary effect of fly ash and palm oil fuel ash on heat of hydration aerated concrete. (United States)

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


    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.

  16. Synthesis and characterization of geopolymer from bottom ash and rice husk ash (United States)

    Anggarini, Ufafa; Sukmana, Ndaru C.


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

  17. Methanol Cannon Demonstrations Revisited. (United States)

    Dolson, David A.; And Others


    Describes two variations on the traditional methanol cannon demonstration. The first variation is a chain reaction using real metal chains. The second example involves using easily available components to produce sequential explosions that can be musical in nature. (AIM)

  18. TENCompetence tool demonstration

    NARCIS (Netherlands)

    Kluijfhout, Eric


    Kluijfhout, E. (2009). TENCompetence tool demonstration. Presented at Zorgacademie Parkstad (Health Academy Parkstad), Limburg Leisure Academy, Life Long Learning Limburg and a number of regional educational institutions. May, 18, 2009, Heerlen, The Netherlands: Open University of the Netherlands, T

  19. Land Management Research Demonstration (United States)

    US Fish and Wildlife Service, Department of the Interior — In 2002, Neal Smith National Wildlife Refuge became one of the first Land Management and Research Demonstration (LMRD) sites. These sites are intended to serve as...

  20. Pancreaticopleural fistula : CT demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Hahm, Jin Kyeung [Chuncheon Medical Center, ChunChon (Korea, Republic of)


    In patients with chronic pancreatitis, the pancreaticopleural fistula is known to cause recurrent exudative or hemorrhagic pleural effusions. These are often large in volume and require treatment, unlike the effusions in acute pancreatitis. Diagnosis can be made either by the finding of elevated pleural fluid amylase level or, using imaging studies, by the direct demonstration of the fistulous tract. We report two cases of pancreaticopleural fistula demonstrated by computed tomography.

  1. Education Payload Operation - Demonstrations (United States)

    Keil, Matthew


    Education Payload Operation - Demonstrations (EPO-Demos) are recorded video education demonstrations performed on the International Space Station (ISS) by crewmembers using hardware already onboard the ISS. EPO-Demos are videotaped, edited, and used to enhance existing NASA education resources and programs for educators and students in grades K-12. EPO-Demos are designed to support the NASA mission to inspire the next generation of explorers.

  2. Edible Astronomy Demonstrations (United States)

    Lubowich, Donald A.


    Astronomy demonstrations with edible ingredients are an effective way to increase student interest and knowledge of astronomical concepts. This approach has been successful with all age groups from elementary school through college students - and the students remember these demonstrations after they are presented. In this poster I describe edible demonstrations I have created to simulate the expansion of the universe (using big-bang chocolate chip cookies); differentiation during the formation of the Earth and planets (using chocolate or chocolate milk with marshmallows, cereal, candy pieces or nuts); and radioactivity/radioactive dating (using popcorn). Other possible demonstrations include: plate tectonics (crackers with peanut butter and jelly); convection (miso soup or hot chocolate); mud flows on Mars (melted chocolate poured over angel food cake); formation of the Galactic disk (pizza); formation of spiral arms (coffee with cream); the curvature of Space (Pringles); constellations patterns with chocolate chips and chocolate chip cookies; planet shaped cookies; star shaped cookies with different colored frostings; coffee or chocolate milk measurement of solar radiation; Oreo cookie lunar phases. Sometimes the students eat the results of the astronomical demonstrations. These demonstrations are an effective teaching tool and can be adapted for cultural, culinary, and ethnic differences among the students.

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

    Directory of Open Access Journals (Sweden)

    Abdulhameed Umar Abubakar


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

  4. Estimation of Volcanic Ash Plume Top Height using AATSR (United States)

    Virtanen, Timo; Kolmonen, Pekka; Sogacheva, Larisa; Sundström, Anu-Maija; Rodriguez, Edith; de Leeuw, Gerrit


    The AATSR Correlation Method (ACM) height estimation algorithm is presented. The algorithm uses Advanced Along Track Scanning Radiometer (AATSR) satellite data to detect volcanic ash plumes and to estimate the plume top height. The height estimate is based on the stereo-viewing capability of the AATSR instrument, which allows to determine the parallax between the satellite's 55° forward and nadir views, and thus the corresponding height. Besides the stereo view, AATSR provides another advantage compared to other satellite based instruments. With AATSR it is possible to detect ash plumes using brightness temperature difference between thermal infrared (TIR) channels centered at 11 and 12 µm. The automatic ash detection makes the algorithm efficient in processing large quantities of data: the height estimate is calculated only for the ash-flagged pixels. In addition, it is possible to study the effect of using different wavelengths in the height estimate, ranging from visible (555 nm) to thermal infrared (12 µm). The ACM algorithm can be applied to the Sea and Land Surface Temperature Radiometer (SLSTR), scheduled for launch at the end of 2015. Accurate information on the volcanic ash position is important for air traffic safety. The ACM algorithm can provide valuable data of both horizontal and vertical ash dispersion. These data may be useful for comparisons with existing volcanic ash dispersion models and retrieval methods. We present ACM plume top height estimate results for the Eyjafjallajökull eruption, and comparisons against available ground based and satellite observations.

  5. Phenolic acids as bioindicators of fly ash deposit revegetation

    Energy Technology Data Exchange (ETDEWEB)

    L. Djurdjevic; M. Mitrovic; P. Pavlovic; G. Gajic; O. Kostic [Institute for Biological Research ' Sinisa Stankovic,' Belgrade (Serbia and Montenegro). Department of Ecology


    The floristic composition, the abundance, and the cover of pioneer plant species of spontaneously formed plant communities and the content of total phenolics and phenolic acids, as humus constituents, of an ash deposit after 7 years of recultivation were studied. The restoration of both the soil and the vegetation on the ash deposits of the 'Nikola Tesla-A' thermoelectric power plant in Obrenovac (Serbia) is an extremely slow process. Unfavorable physical and chemical characteristics, the toxicity of fly ash, and extreme microclimatic conditions prevented the development of compact plant cover. The abundance and cover of plants increased from the central part of the deposit towards its edges. Festuca rubra L., Crepis setosa Hall., Erigeron canadensis L., Cirsium arvense (L.) Scop., Calamagrostis epigeios (L.) Roth., and Tamarix gallica L. were the most abundant species, thus giving the highest cover. Humus generated during the decomposition process of plant remains represents a completely new product absent in the ash as the starting material. The amount of total phenolics and phenolic acids in fly ash increased from the center of the deposit towards its edges in correlation with the increase in plant abundance and cover. The presence of phenolic acids indicates the ongoing process of humus formation in the ash, in which the most abundant pioneer plants of spontaneously formed plant communities play the main role. Phenolic compounds can serve as reliable bioindicators in an assessment of the success of the recultivation process of thermoelectric power plants' ash deposits.

  6. Thermal behaviour of ESP ash from municipal solid waste incinerators. (United States)

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


    Stricter environmental regulations demand safer treatment and disposal of incinerator fly ashes. So far no sound technology or a process is available for a sustainable and ecological treatment of the waste incineration ashes, and only partial treatment is practised for temporary and short-term solutions. New processes and technology need to be developed for comprehensive utilization and detoxification of the municipal solid waste (MSW) incinerator residues. To explore the efficiency of thermal stabilisation and controlled vitrification, the thermal behaviour of electrostatic precipitator (ESP) ash was investigated under controlled conditions. The reaction stages are identified with the initial moisture removal, volatilization, melting and slag formation. At the temperature higher than 1100 degrees C, the ESP ashes have a quicker weight loss, and the total weight loss reaches up to 52%, higher than the boiler ash. At 1400 degrees C a salt layer and a homogeneous glassy slag were formed. The effect of thermal treatment on the leaching characteristics of various elements in the ESP ash was evaluated with the availability-leaching test. The leaching values of the vitrified slag are significantly lowered than that of the original ash.

  7. Creep Behaviour of Fly Ash-Based Geopolymer Concrete

    Directory of Open Access Journals (Sweden)

    Wallah S.E.


    Full Text Available Fly ash-based geopolymer concrete is manufactured using fly ash as its source material and does not use Portland cement at all. Beside fly ash, alkaline solution is also utilized to make geopolymer paste which binds the aggregates to form geopolymer concrete. This paper presents the study of creep behaviour of fly ash-based geopolymer concrete. Four series of specimens with various compressive strengths were prepared to study its creep behaviour for the duration of test up to one year. The test method followed the procedures applied for Ordinary Portland Cement (OPC concrete. Test results show that fly ash-based geopolymer concrete undergoes low creep which is generally less than that of OPC concrete. After one year of loading, the results for specific creep of fly ash-based geopolymer concrete in this study ranges from 15 to 29 microstrain for concrete compressive strength 67–40 MPa respectively. From the test results, it is also found out that the creep coefficient of fly ash-based geopolymer concrete is about half of that predicted using Gilbert’s Method for OPC concrete.

  8. Behaviour of peat ash in high-temperature processes

    Energy Technology Data Exchange (ETDEWEB)

    Moilanen, A.


    The ash-forming constituents are in peat as minerals and bound in the organic framework. The kind of binding is dependent on peat type, plant species composition, acidity of the peatland, etc. Studies carried out with brown coal have indicated that the forms of ash occurrence in the fuel have an influence on the slagging ehaviour of ash in the process. The behaviour is also dependent on the reactor type and conditions in the reactor, for example, on the composition of gas atmosphere, on temperature, and gas flows. For example, the reducing conditions affect especially the occurrence of iron in different oxidation degrees in gasification, and this affects further the melting behaviour of ash. In brown coal gasification, as much as a third of the iron content was found to be reduced to metallic iron in the fluid-bed gasifier. To forecast the slagging behaviour of ash, the melting temperatures of ash are measured. Fouling or partial melting of ash cannot always be monitored with standard measuring methods, as these phenomena may start already at temperatures 200 deg C lower than the lowest melting temperature. THey can be studied for example with thermochemical methods.

  9. Mutagenicity and genotoxicity of coal fly ash water leachate

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborty, R.; Mukherjee, A. [University of Calcutta, Calcutta (India). Dept. of Botany


    Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to storage or ash ponds located near power stations. This has lain to waste thousands of hectares of land all over the world. Since leaching is often the cause of off-site contamination and pathway of introduction into the human environment, a study on the genotoxic effects of fly ash leachate is essential. Leachate prepared from the fly ash sample was analyzed for metal content, and tested for mutagenicity and genotoxicity. Analyses of metals show predominance of the metals - sodium, silicon, potassium, calcium, magnesium, iron, manganese, zinc, and sulphate. The Ames Salmonella mutagenicity assay, a short-term bacterial reverse mutation assay, was conducted on two-tester strains of Salmonella typhimurium strains TA97a and TA102. For genotoxicity, the alkaline version of comet assay on fly ash leachate was carried in vitro on human blood cells and in vivo on Nicotiana plants. The leachate was directly mutagenic and induced significantconcentration-dependent increases in DNA damage in whole blood cells, lymphocytes, and in Nicotiana plants. The comet parameters show increases in tail DNA percentage (%), tail length (mu m), and olive tail moment (arbitrary units). Our results indicate that leachate from fly ash dumpsites has the genotoxic potential and may lead to adverse effects on vegetation and on the health of exposed human populations.

  10. Modeling transport and aggregation of volcanic ash particles (United States)

    Costa, Antonio; Folch, Arnau; Macedonio, Giovanni; Durant, Adam


    A complete description of ash aggregation processes in volcanic clouds is an very arduous task and the full coupling of ash transport and ash aggregation models is still computationally prohibitive. A large fraction of fine ash injected in the atmosphere during explosive eruptions aggregate because of complex interactions of surface liquid layers, electrostatic forces, and differences in settling velocities. The formation of aggregates of size and density different from those of the primary particles dramatically changes the sedimentation dynamics and results in lower atmospheric residence times of ash particles and in the formation of secondary maxima of tephra deposit. Volcanic ash transport models should include a full aggregation model accounting for all particle class interaction. However this approach would require prohibitive computational times. Here we present a simplified model for wet aggregation that accounts for both atmospheric and volcanic water transport. The aggregation model assumes a fractal relationship for the number of primary particles in aggregates, average efficiencies factors, and collision frequency functions accounting for Brownian motion, laminar and turbulent fluid shear, and differential settling velocity. We implemented the aggregation model in the WRF+FALL3D coupled modelling system and applied it to different eruptions where aggregation has been recognized to play an important role, such as the August and September 1992 Crater Peak eruptions and the 1980 Mt St Helens eruption. Moreover, understanding aggregation processes in volcanic clouds will contribute to mitigate the risks related with volcanic ash transport and sedimentation.

  11. Stabilization of Expansive Soil by Lime and Fly Ash

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-ru; CAO Xing


    An experimental program was undertaken to study the individual and admixed effects of lime and fly ash on the geotechnical characteristics of expansive soil. Lime and fly ash were added to the expansive soil at 4% -6% and 40% - 50% by dry weight of soil, respectively. Testing specimens were determined and examined in chemical composition, grain size distribution, consistency limits, compaction, CBR ,free swell and swell capacity. The effect of lime and fly ash addition on reducing the swelling potential of an expansive soil is presented.It is revealed that a change of expansive soil texture takes place when lime and fly ash are mixed with expansive soil. Plastic limit increases by mixing lime and liquid limit decreases by mixing fly ash, which decreases plasticity index. As the amount of lime and fly ash is increased, there are an apparent reduction in maximum dry density,free swell and swelling capacity under 50 kPa pressure, and a corresponding increase in the percentage of coarse particles, optimum moisture content and CBR value. Based on the results, it can be concluded that the expansive soil can be successfully stabilized by lime and fly ash.

  12. Carbonatation Influence on Fly Ash and Portland Cement Mortars

    Directory of Open Access Journals (Sweden)

    P.L. Valdez–Tamez


    Full Text Available The influence of carbonation on mortars containing 25% of fly ash instead of the cementitious materials was studied. Mortar cylinder specimens were fabricated for 4 different W/C ratios: 0.35, 0.45, 0.55 and 0.65. Mortars with and without fly ash were subjected to an accelerated carbonation process. Volumetric weight, water absorption, compressive strength, water permeability, pH and mercury intrusion porosimetry of the mortar specimens were determined. Due to the fly ash pozzolanic potential, for all W/C ratios, results of the compressive strength tests at 28 days of the mortars with and without fly ash were similar. Mortars with fly ash presented similar water permeability as mortars without fly ash. PH results showed that alkalinity reduction is lower in mortars with fly ash compared to those containing cement only. In all the mortars, the porosimetric analysis indicated that porosity is reduced due to carbonation. Further more, it is showed the predominance of the macro and mesopores.

  13. Zeolite from fly ash: synthesis and characterization

    Indian Academy of Sciences (India)

    Keka Ojha; Narayan C Pradhan; Amar Nath Samanta


    Coal fly ash was used to synthesize X-type zeolite by alkali fusion followed by hydrothermal treatment. The synthesized zeolite was characterized using various techniques such as X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, BET method for surface area measurement etc. The synthesis conditions were optimized to obtain highly crystalline zeolite with maximum BET surface area. The maximum surface area of the product was found to be 383 m2/g with high purity. The crystallinity of the prepared zeolite was found to change with fusion temperature and a maximum value was obtained at 823 K. The cost of synthesized zeolite was estimated to be almost one-fifth of that of commercial 13X zeolite available in the market.

  14. Fly ash for durable concrete construction

    Energy Technology Data Exchange (ETDEWEB)

    Dhir, R.K. [University of Dundee, Dundee (United Kingdom). Dept. of Civil Engineering


    This is essentially a review paper, bringing together the various studies undertaken at the University of Dundee as well as many others selected from published work. A full range of durability properties have been considered dealing with the effects of fly ash (FA) in concrete. It is shown that the use of FA generally effects improvement in the resistance of concrete to various forms of attack. FA is shown to greatly improve concrete resistance to chloride ingress and to reduce expansion caused by ASR. In the case of sulphate attack the use of FA is recommended. With regard to carbonation, FA can slightly reduce the resistance. It is also shown that FA concrete will benefit more from curing than OPC concrete in developing its resistance to deterioration with age. 78 refs., 8 figs., 5 tabs.

  15. Scrap tire ashes in portland cement production

    Directory of Open Access Journals (Sweden)

    Mónica Adriana Trezza


    Full Text Available Scrap tires are not considered harmful waste, but their stocking and disposal are a potential health and environmental risk. Properly controlled calcinations at high temperatures make tire combustion an interesting alternative due to its high calorific power, comparable to that of fuel-oil. Consequently, using them as an alternative combustible material in cement kilns makes it possible to give it a valuable use. However, it remains to be assured whether the impurities added to the clinker through these fuels do not affect its structure or properties.This paper shows the studies carried out on different clinkers under laboratory conditions with different levels of addition of scrap tire ashes, added by partially replacing traditional fuel in cement kilns.

  16. Concrete with Highly Active Rice Husk Ash

    Institute of Scientific and Technical Information of China (English)

    FENG Qing-ge; LIN Qing-yu; YU Qi-jun; ZHAO San-ying; YANG Lu-feng; Shuichi Sugita


    The overall aim was to investigate the effect of highly active rice husk ash (RHA) produced by an industrial furnace on some properties of concrete. The strength, pore volume and pore distribution of concrete and the Ca(OH)2 content in concrete were investigated by JIS A 1108 (Method of test for compressive strength of concrete), a mercury instrument porosimeter, and the thermogravimetric analysis, respectively. The results show that,with RHA replacement of cement,the compressive strength of concrete is increased evidently;the average pore radius of concrete is greatly decreased, especially the portion of the pores greater than 20nm in radius is decreased while the amount of smaller pores is increased, and the more the RHA replacement, the less the amount of Ca(OH)2 in concrete. The latter two results are the main reasons for the strength enhancement of concrete.

  17. Unmanned aerial vehicles for the assessment and monitoring of environmental contamination: An example from coal ash spills. (United States)

    Messinger, Max; Silman, Miles


    Unmanned aerial vehicles (UAVs) offer new opportunities to monitor pollution and provide valuable information to support remediation. Their low-cost, ease of use, and rapid deployment capability make them ideal for environmental emergency response. Here we present a UAV-based study of the third largest coal ash spill in the United States. Coal ash from coal combustion is a toxic industrial waste material present worldwide. Typically stored in settling ponds in close proximity to waterways, coal ash poses significant risk to the environment and drinking water supplies from both chronic contamination of surface and ground water and catastrophic pond failure. We sought to provide an independent estimate of the volume of coal ash and contaminated water lost during the rupture of the primary coal ash pond at the Dan River Steam Station in Eden, NC, USA and to demonstrate the feasibility of using UAVs to rapidly respond to and measure the volume of spills from ponds or containers that are open to the air. Using structure-from-motion (SfM) imagery analysis techniques, we reconstructed the 3D structure of the pond bottom after the spill, used historical imagery to estimate the pre-spill waterline, and calculated the volume of material lost. We estimated a loss of 66,245 ± 5678 m(3) of ash and contaminated water. The technique used here allows rapid response to environmental emergencies and quantification of their impacts at low cost, and these capabilities will make UAVs a central tool in environmental planning, monitoring, and disaster response.

  18. Removal of Lead(II) Ions from Aqueous Solution Using L. Seed Husk Ash as a Biosorbent. (United States)

    Shi, Bingfang; Zuo, Weiyuan; Zhang, Jinlei; Tong, Haijuan; Zhao, Jinhe


    The removal of heavy metals, especially from wastewater, has attracted significant interest because of their toxicity, tendency to bioaccumulate, and the threat they pose to human life and the environment. Many low-cost sorbents have been investigated for their biosorption capacity toward heavy metals. However, there are no reports available on the removal of Pb(II) from aqueous solution by of L. seed husk ash. In this work, use of seed husk ash for the removal of Pb(II) from wastewater was investigated as a function of contact time and the initial pH of the solution. Kinetics and equilibrium constants were obtained from batch experiments. Our study shows that the adsorption process follows pseudo-second-order kinetics. Moreover, the Langmuir absorption model gave a better fit to the experimental data than the Freundlich equation. The maximum adsorption capacity of the husk ash was 263.10 mg g at 298 K and pH 5.0, and this is higher than the previously reported data obtained using other sorbents. The results obtained confirm that seed husk ash is an effective sorbent for the removal of Pb(II) from aqueous solution. Analysis of infrared spectra of the husk ash after absorption of Pb(II) suggested that OH, C=O, C-O, Si-O-Si, and O-Si-O groups were important for the Pb(II) ion removal. Moreover, practical tests on this biosorbent for Pb(II) removal in real wastewater samples successfully demonstrated that seed husk ash constitutes an efficient and cost-effective technology for the elimination of heavy metals from industrial effluent.

  19. Effective use of fly ash slurry as fill material. (United States)

    Horiuchi, S; Kawaguchi, M; Yasuhara, K


    A lot of effort has been put into increasing coal ash utilization; however, 50% of total amount is disposed of on land and in the sea. Several attempts have been reported recently concerning slurried coal fly ash use for civil engineering materials, such as for structural fill and backfill. The authors have studied this issue for more than 15 years and reported its potential for (1) underwater fills, (2) light weight backfills, and (3) light weight structural fills, through both laboratory tests and construction works. This paper is an overview of the results obtained for slurry, focusing on the following. (1) Coal fly ash reclaimed by slurry placement shows lower compressibility, higher ground density, and higher strength than by the other methods. This higher strength increases stability against liquefaction during earthquake. (2) Higher stability of the fly ash ground formed by slurry placement is caused by higher density and its self-hardening property. (3) Stability of fly ash reclaimed ground can be increased by increasing density and also by strength enhancement by cement addition. (4) Technical data obtained through a man-made island construction project shows the advantages of fly ash slurry in terms of mechanical properties such as higher stability against sliding failure, sufficient ground strength, and also in terms of cost saving. (5) Concentration in leachates from the placed slurry is lower than the Japanese environmental law. (6) In order to enlarge the fly ash slurry application toward a lightweight fill, mixtures of air foam, cement and fly ash were examined. Test results shows sufficient durability of this material against creep failure. This material was then used as lightweight structural fill around a high-rise building, and showed sufficient quality. From the above data, it can be concluded that coal fly ash slurry can be effectively utilized in civil engineering projects.

  20. 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)


    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.

  1. Particle analysis of volcanic ash with Electron Microscopy (United States)

    Lieke, K. I.; Kristensen, T. B.; Koch, C. B.; Korsholm, U. S.; Sørensen, J. H.; Bilde, M.


    Since the airspace closure over Europe due to the Eyjafjalla eruption in 2010, volcanic ash has come more in the focus of atmospheric science. The airspace closure accompanying the Grímsvötn eruption in 2011 clearly indicates that there is still a great need to increase the scientific understanding of the properties and impacts of volcanic ash particles. Determination of particle characteristics, preferably in near real time, serves as an important input to transport models in operational use for decision support and guidance of authorities. We collected particles before and after the Grímsvötn volcanic ash arrived at Copenhagen, Denmark, between 23 May and 31 May 2011, as well as at a number of other locations. The analysis of meteorological conditions shows that the particle collection performed before arrival of the volcanic ash may serve as a good reference sample. We have thus been able to identify significant differences in aerosol chemical composition during a volcanic ash event over Copenhagen. These results are compared to volcanic ash particles collected on Iceland. We provide unique data about single-particle structure, chemical composition, size and morphology of volcanic ash particles. Single-particle analysis by SEM, and mineralogical studies by XRD and TEM prove that the particles are composed of glass of a characteristic composition and small, nm sized minerals attached to the large (up to tens of µm) glass fragments. The derived information about volcanic ash particles can be used by transport models, resulting in improved information to the authorities in case of new volcanic ash events over Scandinavia or Europe.

  2. Utilization of coal ash from fluidized-bed combustion boilers as road base material. Ryudosho boiler sekitan nenshobai no robanzai eno riyo

    Energy Technology Data Exchange (ETDEWEB)

    Ito, H.; Shibata, Y.; Takada, T.; Yamamuro, H. (Kawasaki Heavy Industries, Ltd., Tokyo (Japan))


    The present report reports the technological development to utilize coal ash from the fluidized-bed combustion boiler as a road base material. In case of mass production by low pressure press forming, the following hardening conditions are reported to be appropriate for kneading the ash only with water, curing it with steam and obtaining the higher compressive strength of thus hardened ash than 150kgf/cm[sup 2]: the boiler operational condition is to be adjusted so that the CaO content and char content may exceed 10% and fall bellow 20%, respectively of the coal ash. The kneading water rate is to be set around the plastic limit of coal ash. The duration of precuring and main precuring is to be 6 to 10h, at 30[degree]C and 10 to 15h at 60[degree]C, respectively. Explained is the result of mass production test with kneader, plastic former and crusher of the same structure as the presumed actual ones, and assessment test (laboratory test and field test on the road pavement) on the hardened and crushed ash with the compressive strength of 170kgf/cm[sup 2] as a pavement material. The present report also reports the operational start of a demonstration plant for the base material production. 5 refs., 11 figs., 2 tabs.

  3. DNA damage induced by coal dust, fly and bottom ash from coal combustion evaluated using the micronucleus test and comet assay in vitro. (United States)

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


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

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

    DEFF Research Database (Denmark)

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

    In this literature report is provided a status for the present knowledge level on ash properties when co-firing coal and biomass. The fly ash formed in boilers using co-firing of coal and straw do have a large influence on ash deposit formation, boiler corrosion, fly ash utilization and operation...

  5. Electrodialytic treatment of sewage sludge ash for the recovery of phosphorous and separation of heavy metals

    DEFF Research Database (Denmark)

    Ebbers, Benjamin; Ottosen, Lisbeth M.; Jensen, Pernille Erland;


    in separation from the ash suspension to the anode compartment. Although 96% of the recovered P was mobilized, only 55% was separated from the ash suspension. Less mobilization (m), but better separation (s), from the ash and ash suspension was observed for heavy metals, 78% (m) 69% (s) for Cd; 24% (m) 7% (s...

  6. X-ray powder diffraction-based method for the determination of the glass content and mineralogy of coal (co)-combustion fly ashes

    Energy Technology Data Exchange (ETDEWEB)

    O. Font; N. Moreno; X. Querol; M. Izquierdo; E. Alvarez; S. Diez; J. Elvira; D. Antenucci; H. Nugteren; F. Plana; A. Lopez; P. Coca; F.G. Pena [Institute of Environmental Assessment and Water Research (IDA-CSIC), Barcelona (Spain)


    The relevance of Al-Si glass in a number of fly ash applications, such as use as a pozzolanic material, zeolite synthesis, and geopolymer production, necessitated research towards investigation of methods for an easy and consistent determination of the glass content in this coal (co)-combustion by-products. A glass standard-addition X-ray powder diffraction (XRD)-based method is proposed in this study as an alternative to the non straightforward procedure of conventional methods for determining the amorphous components, mainly by difference of the total mass and the addition of quantified crystalline species. A >99% Al-Si glass slag sample was selected as a standard for glass. A number of glass standard/fly ash mixtures were performed on Fluidized Bed Combustion (FBC) and pulverized coal combustion (PCC) fly ashes and subsequently analyzed by XRD. The method provides results closer to quantitative proportions of the Al-Si amorphous material of this (co)-combustion by-product, with a range of values <3% when compared with those obtained by the conventional Reference Intensity Method (RIM) method, demonstrating suitability and consistence of the procedure. The mineralogy of FBC and PCC fly ash was also investigated using the RIM method. The occurrence and proportions of the crystalline components in fly ash are in line with the combustion technology and their inherent operational parameters, especially the (co)-combustion temperature. The FBC fly ash shows the highest content of relic phases from feed coal (quartz, illite, calcite, and feldspars) and lower contents of amorphous components. The PCC fly ash are characterized by the highest proportions of mullite and Al-Si glass and low contents of quartz an other relict phases. The occurrence and distribution of anhydrite and Fe-oxide species appears to be related to the content of Ca and Fe in the feed fuels, showing slightly higher contents in FBC than in PCC fly ash. 26 refs., 3 figs., 5 tabs.

  7. Usage of fly ash as a coal desulphurization reagent

    Energy Technology Data Exchange (ETDEWEB)

    Yaman, S.; Kuecuekbayrak, S. [Istanbul Technical Univ. (Turkey). Chemical and Metallurgical Engineering Faculty


    This paper covers the direct usage of fly ash to remove sulphur from coal. Experiments were carried out on a high sulphur Turkish lignite. 5 g of fly ash was extracted in 200 ml of water under pressure and the dilute solution containing water extractable parts of fly ash was used as desulphurization reagent. Oxygen pressure was created over desulphurization medium during the extraction period by which dissolved oxygen was concentrated in the solution. Effects of temperature, partial pressure of oxygen, and time were investigated in the ranges of 403--498 K, 0.0--1.5 MPa and 15--90 min, respectively.

  8. CO2 uptake capacity of coal fly ash

    DEFF Research Database (Denmark)

    Mazzella, Alessandro; Errico, Massimiliano; Spiga, Daniela


    Coal ashes are normally considered as a waste obtained by the coal combustion in thermal power plants. Their utilization inside the site where are produced represents an important example of sustainable process integration. The present study was performed to evaluate the application of a gas......% corresponding to a maximum carbonation efficiency of 74%, estimated on the basis of the initial CaO content. The high degree of ash carbonation achieved in the present research, which was conducted under mild conditions, without add of water and without stirring, showed the potential use of coal fly ash in CO2...

  9. Research on municipal solid waste composting with coal ash

    Institute of Scientific and Technical Information of China (English)

    曾光明; 袁兴中; 李彩亭; 黄国和; 李建兵; 尚谦; 陈耀宁


    Considering the fact that there is much coal ash in the municipal solid waste (MSW) in some cities of China, the feasibility of composting in this situation was studied and the effect of content of the coal ash on the composting process and some basic relative technological parameters were investigated. The values of the moisture, the total organic matter, the content of coal ash, the C/N ratio and the ventilation were suggested to be 50%-60%, 40%-60%, 40%-60%, (25∶1)-(35∶1) and 0.05-0.20m3/(min*m3), respectively.

  10. Magmatic and fragmentation controls on volcanic ash surface chemistry (United States)

    Ayris, Paul M.; Diplas, Spyros; Damby, David E.; Hornby, Adrian J.; Cimarelli, Corrado; Delmelle, Pierre; Scheu, Bettina; Dingwell, Donald B.


    The chemical effects of silicate ash ejected by explosive volcanic eruptions on environmental systems are fundamentally mediated by ash particle surfaces. Ash surfaces are a composite product of magmatic properties and fragmentation mechanisms, as well as in-plume and atmospheric alteration processes acting upon those surfaces during and after the eruption. Recent attention has focused on the capacity of alteration processes to shape ash surfaces; most notably, several studies have utilised X-ray photoelectron spectroscopy (XPS), a technique probing the elemental composition and coordination state of atoms within the top 10 nm of ash surfaces, to identify patterns of elemental depletions and enrichments relative to bulk ash chemical composition. Under the presumption of surface and bulk equivalence, any disparities have been previously attributed to surface alteration processes, but the ubiquity of some depletions (e.g., Ca, Fe) across multiple ash studies, irrespective of eruptive origin, could suggest these to be features of the surface produced at the instant of magma fragmentation. To investigate this possibility further, we conducted rapid decompression experiments at different pressure conditions and at ambient and magmatic temperature on porous andesitic rocks. These experiments produced fragmented ash material untouched by secondary alteration, which were compared to particles produced by crushing of large clasts from the same experiments. We investigated a restricted size fraction (63-90 μm) from both fragmented and crushed materials, determining bulk chemistry and mineralogy via XRF, SEM-BSE and EPMA, and investigated the chemical composition of the ash surface by XPS. Analyses suggest that fragmentation under experimental conditions partitioned a greater fraction of plagioclase-rich particles into the selected size fraction, relative to particles produced by crushing. Trends in surface chemical composition in fragmented and crushed particles mirror that

  11. Agricultural uses of alkaline fluidized bed combustion ash: case studies

    Energy Technology Data Exchange (ETDEWEB)

    Stout, W.L.; Daily, M.R.; Nickeson, T.L.; Svendson, R.L.; Thompson, G.P. [USDA-ARS, University Park, PA (United States)


    Successful programmes were developed by Ahlstrom Development Ash Corporation and Air Products and Chemical for using fluidized bed combustion ash as a substitute for agricultural lime on dairy farms in northern New York state and on fruit and nut crops in the San Joaquin Valley of California. The companies developed these programmes by utilizing the methodology developed through USDA-ARS research and working closely with agricultural consultants and regulatory agencies to ensure that the ash applications were both agronomically and environmentally sound. 1 ref.

  12. Solar renovation demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Bruun Joergensen, O. [ed.


    In the framework of the IEA SHC Programme, a Task on building renovation was initiated, `Task 20, Solar Energy in Building Renovation`. In a part of the task, Subtask C `Design of Solar Renovation Projects`, different solar renovation demonstration projects were developed. The objective of Subtask C was to demonstrate the application of advanced solar renovation concepts on real buildings. This report documents 16 different solar renovation demonstration projects including the design processes of the projects. The projects include the renovation of houses, schools, laboratories, and factories. Several solar techniques were used: building integrated solar collectors, glazed balconies, ventilated solar walls, transparent insulation, second skin facades, daylight elements and photovoltaic systems. These techniques are used in several simple as well as more complex system designs. (au)

  13. Gigashot Optical Laser Demonstrator

    Energy Technology Data Exchange (ETDEWEB)

    Deri, R. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)


    The Gigashot Optical Laser Demonstrator (GOLD) project has demonstrated a novel optical amplifier for high energy pulsed lasers operating at high repetition rates. The amplifier stores enough pump energy to support >10 J of laser output, and employs conduction cooling for thermal management to avoid the need for expensive and bulky high-pressure helium subsystems. A prototype amplifier was fabricated, pumped with diode light at 885 nm, and characterized. Experimental results show that the amplifier provides sufficient small-signal gain and sufficiently low wavefront and birefringence impairments to prove useful in laser systems, at repetition rates up to 60 Hz.

  14. Demonstrating Supernova Remnant Evolution (United States)

    Leahy, Denis A.; Williams, Jacqueline


    We have created a software tool to calculate at display supernova remnant evolution which includes all stages from early ejecta dominated phase to late-time merging with the interstellar medium. The software was created using Python, and can be distributed as Python code, or as an executable file. The purpose of the software is to demonstrate the different phases and transitions that a supernova remnant undergoes, and will be used in upper level undergraduate astrophysics courses as a teaching tool. The usage of the software and its graphical user interface will be demonstrated.

  15. Demonstrating marketing accountability. (United States)

    Gombeski, William R; Britt, Jason; Taylor, Jan; Riggs, Karen; Wray, Tanya; Adkins, Wanda; Springate, Suzanne


    Pressure on health care marketers to demonstrate effectiveness of their strategies and show their contribution to organizational goals is growing. A seven-tiered model based on the concepts of structure (having the right people, systems), process (doing the right things in the right way), and outcomes (results) is discussed. Examples of measures for each tier are provided and the benefits of using the model as a tool for measuring, organizing, tracking, and communicating appropriate information are provided. The model also provides a framework for helping management understand marketing's value and can serve as a vehicle for demonstrating marketing accountability.

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

    Energy Technology Data Exchange (ETDEWEB)

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


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

  17. Characterisation and management of ash produced in the hospital waste incinerator of Athens, Greece

    Energy Technology Data Exchange (ETDEWEB)

    Kougemitrou, Irene [Harokopio University of Athens, 70 El. Venizelou Str., 17671 Athens (Greece); Godelitsas, Athanasios, E-mail: [University of Athens, Panepistimioupoli Zographou, 15784 Athens (Greece); Tsabaris, Christos [Hellenic Center of Marine Research, 19013 Anavyssos (Greece); Stathopoulos, Vassilis [Technological Educational Institute of Chalkida, 34400 Psahna (Greece); Papandreou, Andreas [CERECO S.A. Ceramics and Refractories Technological Development Company, 34100 Chalkida (Greece); Gamaletsos, Platon [University of Athens, Panepistimioupoli Zographou, 15784 Athens (Greece); Economou, George [Institute of Geology and Mineral Exploration, Olympic Village, 13677 Acharnai (Greece); Papadopoulos, Dimitris [APOTEFROTIRAS S.A., Ano Liossia, 19200 Elefsina (Greece)


    Bottom and fly ash samples (BASH and FASH) from the APOTEFROTIRAS S.A. medical waste incinerator (Athens, Greece) were investigated. Powder-XRD data and geochemical diagrams showed BASH to be an amorphous material, analogous to basaltic glass, and FASH consisting of crystalline compounds (mainly CaClOH). Bulk analyses by ICP-MS and point analyses by SEM-EDS indicated a high content of heavy metals, such as Fe, Cu and Cr, in both samples. However, BASH was highly enriched in Ni while FASH was additionally enriched in Zn and Pb. Gamma-ray measurements showed that the radioactivity of both ash samples, due to natural and artificial radionuclides ({sup 137}Cs, {sup 57}Co), was within the permissible levels recommended by IAEA. According to EN-type leaching tests, BASH was practically inert with regard to the mobility of the hazardous elements in aqueous media. FASH, however, showed a relatively high EN (and TCLP) leachability with regard to Pb and Zn. Finally, the stabilisation method, suggested for the treatment of FASH, included compression of the powder into briquettes using an appropriate machine and embedding the briquettes into pozzolanic cement blocks. After this treatment, TCLP and EN-type tests showed minimal release of Pb and Zn, thereby demonstrating a reliable management of ash waste.

  18. Seismicity of block-and-ash flows occurring during the 2006 eruption of Augustine Volcano, Alaska (United States)

    DeRoin, Nicole; McNutt, Stephen R.; Sentman, Davis D.; Reyes, Celso


    In January 2006, Augustine Volcano began erupting following an increase in seismicity that was first noted in late April 2005. Thirteen large explosive eruptions of Augustine occurred from January 11 to 28, 2006, followed by a continuously erupting phase and then by a dome growth phase in which numerous pyroclastic flows and block-and-ash flows occurred. As a new steep-sided and unstable dome grew in spring 2006, rockfalls and related events, likely block-and-ash flows, dominated the seismic record. Relative amplitudes at pairs of seismic stations for 68 block-and-ash flow events were examined to constrain locations of the flow-events. Higher amplitudes were associated with events closer to a given station. These relations were confirmed by images collected on a low-light camera. Captured images show a correlation between flow direction and seismic amplitude ratios from nearby stations AUE and AUW. Seismic amplitudes and energies of the flow signals, measured in several different ways, were found to correlate with the surface areas and run-out distances of the flows. The ML range of rockfalls was 0.1 to 1.1, and seismic efficiencies were estimated to be much less than 1%. Particle motion analyses showed that the seismic waves contained both body waves and surface waves and demonstrate that the flows were acting as moving sources with velocities of 30-93 m/s.

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

    DEFF Research Database (Denmark)

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


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

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

    DEFF Research Database (Denmark)

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


    Wood ash (WA) is the residue generated during incineration of wood and wood products. The WAs in focus of this work are from incineration of virgin wood. Physical and chemical properties of WA vary significantly depending on many factors related to the wood species and the incineration process...... from the differences in ash characteristics to the properties of the mortar samples. The characteristics of the ashes did vary considerably. For example, one ash had very high loss on ignition (LoI) of 14% compared to 3% for the other ashes. Ash solubility in water ranged from 18% to 28%. Two...... of the ashes were dry and sampled just after the incineration, whereas one ash had a water content of 15%, because the ash was sprayed with water to avoid dust during ash handling at the incineration plant. Regardless of replacing cement or sand with WAs, the compressive strength decreased compared...