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Showing papers on "Fly ash published in 1983"



Journal ArticleDOI
TL;DR: Inventory procedures for fine-particle trace-metals emissions are developed that assist aerosol source apportionment by receptor modeling techniques and it is shown how sparse routine air monitoring data sets on a very few trace elements can be used in chemical element balance calculations once emission inventory data have shown that avery few source signatures do complete a mass balance on those chemical elements that were measured.
Abstract: Inventory procedures for fine-particle trace-metals emissions are developed that assist aerosol source apportionment by receptor modeling techniques. It is shown how sparse routine air monitoring data sets on a very few trace elements can be used in chemical element balance calculations once emission inventory data have shown that a very few source signatures do complete a mass balance on those chemical elements that were measured. Methods developed are tested in the South Coast Air Basin of California for the year 1976, where it is shown that over 80% of the fine lead emissions comes from highway traffic, 81% of the nickel arises from fuel oil fly ash, and more than 90% of the iron and manganese comes from soil-like materials. With use of readily available trace element data from local and Federal monitoring networks, it is found that most monitoring sites are exposed to aerosol containing about 20% highway vehicle exhaust, 1-2% fuel oil fly ash, 20-50% soil dust or road dust, with sulfates and nitrates each present at about 15% of total mass.

96 citations


Journal ArticleDOI
TL;DR: In this paper, fly ash from a coal-fired power station was incorporated with each of a 'fine' (0.2-0.5 mm) and 'coarse' (1.4-2.0 mm) sand fraction to give mixtures containing 0, 10, 20, 30, 40, 50, 75 and 100% fly ash by weight.
Abstract: Fly ash from a coal-fired power station was incorporated with each of a 'fine' (0.2-0.5 mm) and 'coarse' (1.4-2.0 mm) sand fraction to give mixtures containing 0, 10, 20, 30, 40, 50, 75 and 100% fly ash by weight. The addition of 10% by weight of ash increased the available water capacity by factors of 7.2 (1.0-7.2% by weight) and 13.5 (0.4-5.4% by weight) for the 'fine' and 'coarse' sands respectively. Subsequent additional 10% increments of ash increased the capacity by smaller amounts. The saturated hydraulic conductivity of the sands decreased markedly with ash addition. The changes in available water capacity and hydraulic conductivity were associated with an increase in capillary pores at the expense of non-capillary pores. Addition of fly ash to both sand fractions resulted in a bilinear relationship between void ratio (volume voids/volume solids) and fly ash percentage in the mixes which was closely related to that theoretically predicted for binary mixtures. The measured void ratios of the mixes exhibited minimum values at 36% and 20% ash by volume for the 'fine' and 'coarse' sand mixes respectively, which compared with the theoretical void ratios for these mixes of 27% and 23% respectively.

87 citations



Journal ArticleDOI
TL;DR: In this paper, the authors evaluated the accuracy and reliability of intact microcosms to predict trace element enrichment in field-grown crops due to fly ash amendment in both laboratory microcosm and field plots.

60 citations


Patent
15 Aug 1983
TL;DR: A process for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous is described in this paper, with the fly ash having a silicate base and containing surface deposits of the trace metals as oxides, chlorides or the like.
Abstract: A process for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous, the fly ash having a silicate base and containing surface deposits of the trace metals as oxides, chlorides or the like, with the process being carried out by contacting the fly ash with AlCl 3 in an alkali halide melt to react the trace metals with the AlCl 3 to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

59 citations


DOI
01 May 1983
TL;DR: In this paper, the effect of fly ash on air-void stability was evaluated in concrete with both portland cement and fly ash and the results indicated that air contents of concrete containing Class C fly ash appear to be more stable than those of concrete with Class F fly ash.
Abstract: Concrete containing both portland cement and fly ash were evaluated to determine the effect of fly ash on air-void stability. Tests indicate that air contents of concrete containing Class C fly ash appear to be more stable than those of concrete containing Class F fly ash. The higher the organic matter content of a fly ash, the higher will be the air-entraining admixture requirement for concrete in which the admixture is used. The higher the air-entraining admixture requirement, the greater is the air loss on extended mixing. Even though the air volume is reduced the spacing factor, specific surface, and number of voids are little affected. The "Foam Index" test was conducted and found to be a satisfactory method for checking air-entraining admixture requirements. (Author)

59 citations


Journal ArticleDOI
TL;DR: The rates of leaching of several transition-metal ions from coal fly ash by pH 7.4 solutions of the chelating agents citric acid, EDTA, Listidine and glycine have been measured as part of an investigation of the potential health effects of inhaled fly ash.
Abstract: The rates of leaching of several transition-metal ions from coal fly ash by pH 74 solutions of the chelating agents citric acid, EDTA, Listidine and glycine have been measured as part of an investigation of the potential health effects of inhaled fly ash The results are compared to leaching of the same fly ash by 05M HCl, 010 M pH 74 Tris buffer, 05 M NH/sub 4/OH, and canine serum For the trace elements, Zn, Mn, G, Ni, and Cu, the initial leaching rates with 05 M HCl range from 350 to 850 ppm/d The rates drop by 1-2 orders of magnitude within 24 h and then level off at 1-10 ppm/d The initial rates with EDTA and citric acid are also high, 100-400 ppm/d, but they fall off even more rapidly than the HCl leaching rates The leaching of vanadium is exceptionally rapid, with initial rates of 1000-3000 ppm/d

56 citations


Journal ArticleDOI
TL;DR: Dose calculations suggest that fly ash will contribute to a reduction in effective dose equivalent due to the reduced radon-exhalation rate in concrete containing fly ash.
Abstract: The radiological consequences of using fly ash as a component of cement are discussed. Measurements of the activity concentrations of the fly ash and cement are reported together with measurements of emanation coefficients and exhalation rates. The radon-exhalation rate was found to be signi

54 citations


Journal ArticleDOI
TL;DR: In this paper, a theoretical model for adsorption of polycyclic aromatic hydrocarbons (PAH) on fly ash has been examined experimentally, and a new model which is based on these experimental results is proposed.

49 citations



Journal ArticleDOI
01 Sep 1983
TL;DR: In this article, extensive data is presented on the properties, in the fresh and hardened state, of fly ash concrete containing normal weight and light weight aggregates suitable for structural applications, and tests on reinforced concrete beams and slabs are reported to show that fly ashcrete can exhibit structural performance similar to that of conventional concrete with adequate safety factors and predicted by existing codes.
Abstract: Extensive data are presented on the properties, in the fresh and hardened state, of fly ash concrete containing normal weight and light weight aggregates suitable for structural applications. Tests on reinforced concrete beams and slabs are reported to show that fly ash concrete can exhibit structural performance similar to that of conventional concrete with adequate safety factors and predicted by existing codes.

01 Sep 1983
TL;DR: In this paper, the effectiveness of substituting kiln dusts for hydrated lime in lime-fly ash-aggregate road base systems has been investigated, and the results of compressive strength tests were performed.
Abstract: Production of lime and portland cement results in the annual generation of more than 20 million tons of kiln dust, mostly cement kiln dust. The purpose of this investigation was to determine the effectiveness of substituting kiln dusts for hydrated lime in lime-fly ash-aggregate road base systems. A total of 45 kilm dust samples, including 33 cement dusts and 12 lime dusts, were obtained in accordance with a standard sampling procedure. In addition, 18 fly ashes (including 5 Class C ash samples) and 6 aggregates were included in the sampling program. Kiln dust and fly ash samples were characterized by Trow, Ltd. to determine physical properties and chemical, as well as mineralogical, composition. Optimum kiln dust-fly ash ratios were developed for 66 mix combinations. Kiln dust-fly ash-aggregate compressive strength tests were performed. Engineering properties (durability, volume stability, etc.) of optimum mix combinations were tested and compared with conventional lime-fly ash-aggregate mixtures. Most kiln dust-fly ash-aggregate mixes were comparable to, and in many cases demonstrated higher early strength development than, lime-fly ash-aggregate mixes. Optimum mix strengths for kiln dust-fly ash-aggregate compositions were generally attained at kiln dust-fly ash ratios of 2:1 using cement liln dust and 1:1 using lime liln dust. By contrast, most lime-fly ash-aggregate mixes have lime-fly ash ratios of 1:3 or 1:4. Therefore, higher concentrations of kiln dust are required compared to commercial lime. Mixes containing Class C fly ash developed higher strengths than comparable mixes with Class F fly ash. (FHWA)


Journal ArticleDOI
TL;DR: Fly ash residues from several sites in which solid municipal refuse is being incinerated for energy production were found to contain excessive amounts of cadmium and/or lead according to an empirical extraction test developed by the Environmental Protection Agency.
Abstract: Fly ash residues from several sites in which solid municipal refuse is being incinerated for energy production were found to contain excessive amounts of cadmium and/or lead according to an empirical extraction test (0.5 N acetic acid) developed by the Environmental Protection Agency. Samples of associated bottom ashes contained acceptable levels of Cd and Pb, but several were marginal with respect to Pb content. Leaching tests clearly demonstrated that Cd and, to a lesser extent, Pb content were mobile in soil when applied in a fly ash matrix. The high chloride content (10-12%), which is characteristic of these ashes, resulted in metal complexation and enhanced Cd and Pb mobility in soil. Normally these elements are relatively immobile in soils when applied as inorganic salts or contained in municipal sewage sludge. Plant uptake of Cd and Pb in a greenhouse test was marked when fly or finely ground bottom ashes were soil applied. Phytotoxicity of fly ash appeared to be associated with the high salt content rather than with a specific metal.


Journal ArticleDOI
TL;DR: The tolerable charring temperature for samples containing arsenic can be raised to 1300°C when palladium is added as a matrix modifier as mentioned in this paper, and the sensitivity for arsenic is 50% greater than that in the presence of nickel.

Journal ArticleDOI
TL;DR: In vitro macrophage assays demonstrate that the finest coal fly ash particles are the most cytotoxic; the cytotoxicity is significantly less than that of alpha-quartz, the positive control particle.
Abstract: Studies were performed to compare the physical and chemical characteristics and the in vitro macrophage cytotoxicity of oil and coal fly ash. Sampling methodology was developed to collect size-fractionated particulate matter from the smokestack of either a coal-fired or an oil-fired power plant. Morphological studies demonstrated particle heterogeneity, although most coal fly ash particles appeared to be spherical. Oil fly ash contained two major morphologies; nonopaque amorphous particles and opaque amorphous particles. Elemental analysis indicates that the coal ash is predominantly composed of aluminosilicate particles, while the oil ash is predominantly inorganic sulfates and carbonaceous particles. In vitro macrophage assays demonstrate that the finest coal fly ash particles are the most cytotoxic; the cytotoxicity is significantly less than that of alpha-quartz, the positive control particle. In contrast, the oil fly ash particles are more cytotoxic than quartz. The cytotoxicity of oil fly ash is due to soluble components, possibly vanadium salts.


Journal ArticleDOI
TL;DR: Fluidized bed combustion ash was similar to PCC ash in minor and trace element composition, but AFBC ash showed less size dependence of elemental composition, and Bulk particle elemental composition varied with sampling position within the effluent stream.
Abstract: Trace element constituents in fly ash from an experimental atmospheric fluidized bed combustor (AFBC) are reported and compared with pulverized coal combustor (PCC) data and those from other fluidized bed combustors. Bulk and size-separated particles were collected and analyzed using spark source mass spectrometry. Fluidized bed combustion ash was similar to PCC ash in minor and trace element composition, but AFBC ash showed less size dependence of elemental composition. Bulk particle elemental composition varied with sampling position within the effluent stream. Penetration of elements through each cleanup stage and elemental enrichment were a function of the cleanup stage and the element under consideration.

Journal ArticleDOI
Prabir Basu1, A. Sarka1
01 Aug 1983-Fuel
TL;DR: In this article, the defluidization behavior of ash derived from Indian coal by combustion in a fluidized bed has been studied Sintering temperatures for ash in several ranges of particle size were measured with a dilatometer in agreement with the earlier work on other coals.

Patent
01 Feb 1983
TL;DR: In this paper, a method for enhancing the efficiency of fly ash collection in an electrostatic precipitator by lowering the resistivity of the fly ash particles in the flue gas is presented.
Abstract: A method is provided for enhancing the efficiency of fly ash collection in an electrostatic precipitator by lowering the resistivity of the fly ash particles in the flue gas, comprising the steps of introducing an aqueous solution of ammonium sulfate or ammonium bisulfate into a slipstream of hot gas in a chamber external to the main flue gas duct wherein thermal decomposition is effected and distributing the decomposition products into the main flue gas stream exiting from the air preheater at a point upstream from the electrostatic precipitator.

Journal ArticleDOI
01 Aug 1983-Fuel
TL;DR: In this paper, a scheme for the separation of compounds in size-fractionated fly ash by linear density gradients has been developed for identifying minor crystalline components in fly ash.

Journal ArticleDOI
TL;DR: The suitability of fine tailings from eight British collieries and a number of coal ash materials as feeds for alumina recovery by acid leaching routes has been studied in this article.

Journal ArticleDOI
John Cairns1, D S Cherry1
TL;DR: A combined effort of field receiving system monitoring and field located laboratory and formal laboratory bioassay testing was used to evaluate and compare responses of fish and the Asiatic clam (Corbicula fluminea) to cower plant discharges as mentioned in this paper.

Journal ArticleDOI
TL;DR: In this paper, the presence of polychlorinated dibenzo-p-dioxins and polychlorobenzenes (BPCS) on fly ash from municipal incinerators may be the result of combustion of polyvinyl chloride (PVC).

Journal ArticleDOI
TL;DR: In this article, the catalytic and photocatalytic activity of two samples of fly ash from two different coal-fired power plants have been demonstrated for two reactions of environmental significance, namely, the heterogeneous SO 2 oxidation in a smog chamber and the photochemical degradation of two polynuclear aromatic hydrocarbons adsorbed onto the fly ashes.

Journal ArticleDOI
TL;DR: In this article, the element contents of As, Cd, Co, Cu, Fe, Mn, Hg, Na, Pb und Zn of a fly ash from pulverised coal are certified.
Abstract: The element contents of As, Cd, Co, Cu, Fe, Mn, Hg, Na, Pb und Zn of a fly ash from pulverised coal are certified. The procedures and their results for the homogenisation, the contamination and homogeneity checks and the analytical campaign are reported. The certified mass fractions and indicative values for Cr, Ni, Th, V and water soluble sulphate are given. The work was carried out within the framework of the activities of the Community Bureau of Reference (BCR) of the Commission of the European Communities.

Patent
Joseph G. Savins1
19 Jul 1983
TL;DR: In this article, a method for removing the ash mineral matter content of coal and transporting the ash free coal from the point of ash removal to a coal use point comprising grinding run-of-mine coal to a desired particle size, mixing the coal particles with water and liquid carbon dioxide in a vessel in a swirling, fluidized state at a pressure, temperature, and for a residence time sufficient to free substantially all of the coal mineral matter from the coal and form an ash-mineral matter slurry, separating the ash-free coal particles from the slurry by froth float
Abstract: A method for removing the ash mineral matter content of coal and transporting the ash free coal from the point of ash removal to a coal use point comprising grinding run-of-mine coal to a desired particle size, mixing the coal particles with water and liquid carbon dioxide in a vessel in a swirling, fluidized state at a pressure, temperature, and for a residence time sufficient to free substantially all of the ash mineral matter from the coal and form an ash free coal/mineral matter slurry, separating the ash free coal particles from the slurry by froth floatation, drying the ash free coal particles, forming a slurry of the ash free coal particles with liquid carbon dioxide, transporting the ash free coal/liquid carbon dioxide slurry by pipeline to a coal use point, deslurrying the ash free coal/liquid carbon dioxide slurry, recovering the ash free coal particles for intended use and recycling the coal-free liquid carbon dioxide recovered from deslurrying for treating additional coal in the ash removal step.