04680 Use of ash from fluidized-bed coal combustion

04680 Use of ash from fluidized-bed coal combustion

05 solutions in a closed system. The zeolite conversion was studied as a function of temprraturc, reaction time and solution concentration. The zeolit...

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05 solutions in a closed system. The zeolite conversion was studied as a function of temprraturc, reaction time and solution concentration. The zeolite\ synthesized were NaPI, NaP derivatives, analcime, gmelinite and nephclinc hydrate after NaOH activation, and phillipsite after KOH activation. Subsequent experiments focused on short reaction times for high conversion efficiencies and monomineral synthesis of zeolites. High synthesis efficiencies for NaPl zeolite and analcime were obtained with the flv ash types studied. The results highlight the importance of the mineralogical cornpositron of the fly ash.

Tests of pitch, produced from the mixture resin and remainders after oil pyrolysis

97104676

Thermal behavior tar and petroleum pitches

of extrographic

fractions

Usability

of industrial

Kaloc, M. (‘I trl. Carhorl Ca&rruceo~~.\ Conrpos. Mater.: Strut..Prop. R&t.. /C‘ouf./. IYYS, (Pub. lYY6). 247-251. Edited by Palmer, K. R. et al.. World icientific, Singapore. In the production of various kinds of pitch. coal tar presents a very significant raw material, which may he used as the hinder for different industrial carbons. According to the auhsequent processing and the use of the final component, various requirements are put on its quality which affects some technical and technological factors. This contribution evaluates the properties of a number of Czech coal tars. The tars have heen ascertained to contain a great amount of the substances insoluble in toluene (TI) and quinoline (Ql). Their presence affects the processing needed to form coke. The properties of the final pitch depend on the origin, the properties and the hehaviour of the compounds insoluble in quinoline. These are always contained in the coal tar and they remain in the pitch after its distillation. These Ql are divided into the primary and secondary parts, hoth of which influence the final quality parameters.

The use of alkali-activated fly ash grouts for the remediation of AMD from underground mines Eaker, C. et rrl. Pmt. Amrr. Int. Pittshwgh Coal Cmf., 1996. 13th, (l), 72Y-

97104679

733. Laboratory studies were conducted using several fly ash grout formulations to determine the optimum grout for an underground mine environment, in preparation for a field demonstration. This paper discusses the portion of the overall project designed to examine grout-acid mine drainage (AMD) interactions including neutralization, leaching, and armouring of the grouts. Leaching tests were performed to study the effects of fly ash grout and AMD, including the effects of armouring. A study of the feasibility of in-.vitu acid mine drainage treatment by injecting alkali-activated fly ash grout into an underground mine is the aim of this project.

Use of ash from fluidized-bed

coal combustion

Kusnierz, S. and Smolka. W. Knrho-Ener-gocherni~ui-~k~l., 1996. 41, (7), 239-244. (In Polish) The paper presents a method for granulation of fluidized bed combustion coal ash. The granules are suitable for transportation and may he stored in mine excavations.

97104681 way repairs

Use of clean coal combustion

by-products

of pitches

obtained

by various

Banak-Tahkowska, J. and Tomaszkiewicz-Potepa. A. Kurho-Emqoclrent/cd-Ekol., 1997, 42, (3). 118-119. (In Polish) Studies have been made into investigations of pitches received during the distillation or primary tars to 3lO’C as well as the oxygen-thermal processing of primary tars.

of coal

carbon

97104680

properties

methods

97104683

of coal tar for the preparation

Useful

97104682

Bermejo. J. et al. F[rc/. 1997, 76, (2). 179-187. Extrographical fractionation was performed on two coal-tar pitches and a petroleum pitch on a preparative scale. The chemical composition of the fractions was determined hy elemental analysis, FT-IR, ‘H-NMR and solidstate “C-NMR spectroscopies and no.-average molecular weight (Mn) determination. Their thermal hehaviour was studied using thermal analysis techniques. The fractions were also carbonized and the resulting cokes characterized hy optical microscopy. Exo- and endothermic effects shown by the DTA curves of extrographical fractions of the pitches were associated with the physicochemical phenomena expected t<) occur during pyrolysis of their respectively constituents. The composition of a pitch and the reactivity of its constituents were reflected in the degree of overlap between the endothermic effect of volatilization and the exothermicity of polymerization The lowest reactivity among pitch constituents corresponds to medium-molecule-size neutral aromatics, whereas mixtures of basic nitrogen compounds and other N-O-mixed heterocycles seem to be optimal for obtaining a well-structured coke. Conversely, an excessive increase in the reactivity of pitch constituents hringa about a decrease in coke optical texture. 97104676

consisted of a field-compacted mixture of soil and FGD ash in approximately equal proportions. The third section was constructed of compacted FGD by-product. All three test sections were capped by a layer of compacted boiler ash or crushed stone to provide a temporary wearing surface. Measurements of slope movement as well as water quality and levels were being made at the site to evaluate long-term embankment performance. The completion of this experiment should lead to increased acceptance of FGD by-products in construction projects. By avoiding some of the disposal costs for the material and the reduced reliance on alternative engineering materials produces monetary savings.

of coal

Itskov. M. L. et trl. Li$r Mel., 1997, 5SY-562. The paper describes laboratory investigations and Soderherg pot tests of anode paste, produced using a mixture of coal-tar and petroleum pitch. The emissions of carcinogens. namely, benzo(a)pyrene. from the surface of anode were conaidcrahly decreased. 97104677

Nuclear fuels (scientific, technical)

in high-

Payettea. R. M. et 01. Fuel, 1997, 76, (8). 749-753. A by-product of dry flue gas desulfurization (FGD) was utilized in the reconstruction of the failed portion of a highway embankment. To evaluate the suitability of FGD by-products in this type of project, the site of the repair was divided into three test sections. in the first section, the soil removed from the slide area was recompacted and replaced according to standard construction practices. In the second section, the embankment

concrete

Worldwide production and other products

of coal ash and utilization

in

Manz, 0. E. Fuel, 1997. 76, (S), h91-hY6. Coal ash production and utilization in the world is discussed and a countryby-country survey of coal ash utilization in concrete.

05

NUCLEAR Scientific.

FUELS

Technical

97104684 Chemical characterization of solid graphitic carbonaceous matter associated with the Oklo natural fission reactors and uranium ore deposits, Gabon (West Africa) (radioactive waste storage) Rigali, M. J. 1997. 188 pp. Avail. UMI, Ahstr. Ozt.. B., 1998, 58, (58). 1756.

97104685 experimental core

Order

No. DAY7294.17.

From miss.

Concept and basic performance of an in-pile reactor for fast breeder reactors using fast driver

Obara, T. and Sekimoto. H. Am. Nucl. Etuqy, 1997, 47, (I-4), 14Yl1513. Possible use of an in-pile experimental reactor for fast breeder reactors, using a fast driver core, is explored. The driver core is composed of a particle bed with diluted fuel. The results show the reactor exhibits performance characteristics that are difficult for conventional thermal inpile experimental reactors in large power excursion experiments to achieve. Thus, this technology offers attractive advantages in the in-pile experiments for fast breeder reactors.

97104686 Core and plant design of the power reactor cooled and moderated by supercritical light water with single tube water rods Dobashi, K. et al. Am. Nucl. Enrrgy, 1997, 24, (lh), 1281-1300. The paper details the design of a reactor cooled and moderated by supercritical light water with single tube water rods. In this once-through direct cycle, the whole coolant which flows once through the core is fed to the turbine. This reactor is much simpler than the current light water reactors LWRs, improving its economy. When evaluating the average outlet coolant temperature the mixing of hot and cold coolant from the fuel assemblies should be taken into account. Nuclear and thermal hydraulic analysis of the whole core was carried out, taking into consideration the effect of coolant density feedback to the radial power distribution. The flow rate in the outer region was reduced by the orifice to maximize the outlet coolant temperature. The average outlet temperature was 397’ C, which is only 12°C lower than that of the hottest channel since the density feedback flattens the radial power distribution. Axial and local peaking factors were also evaluated. A steam cycle including reheaters, turbines and feedwater heaters was designed for estimating the thermal efficiency. The reactor with orifices has 40.7% thermal efficiency and 1013 MW electric power. Greater electric power can be reached in the core without orifices and channel boxes since the channel boxes can be replaced with additional fuel rods. The decrease in the average outlet coolant temperature is only 3°C from the core with the orifices.

97104687 Energy, exergy and thermoeconomic analysis of the effects of fossil-fuel superheating in nuclear power plants Liar, N. Enera Confers. Mpzt, 1997. 38, (lS-17), 1.585-1599. A full size nuclear plant with fossil-fuel superheat, designed with reference to information from Indian Point I, is investigated in this paper. The effect of superheat on hoth energy and exergy performance, as well as on the

Fuel and Energy Abstracts

November

1997

405