Showing papers in "Fuel in 1972"

TL;DR: The porosity of 40 × 70 mesh size American coals, varying in rank from anthracite to lignite, has been studied using the following characterization techniques: gas adsorption, helium displacement, and mercury porosimetry.

TL;DR: The utility of the reflectance of the vitrinite component of coals as a criterion of degree of coalification has been investigated in this article, and it is proposed that they be included in standard classification systems as supplementary criteria of rank.

TL;DR: In this article, the authors investigated the mechanism of a process for removing water as liquid from soft brown coals and found that the removal of liquid water is initiated principally by a disruption of the coal/water interactions caused by the thermal destruction of functional groups.

TL;DR: In this paper, structural properties of pulverized semi-anthracite at various stages of combustion at temperatures in the range 1400-2200 K were made of four size-graded fractions of the particles (mass-median sizes 78, 49, 22 and 6 μm).

TL;DR: In this paper, the optical properties of three vitrinite-rich coals (carbon, daf: 82.5, 88.0 and 93.1%), carbonized at temperature intervals of 25 °C over the greater part of the range 20-950 °C using a heating rate of 2.45 °C/min.

TL;DR: In this article, the laser-Raman spectra of coals, carbons, and graphites have two lines at about the same frequencies as the infra-red bands.

TL;DR: In this article, it was suggested that the apparent increase of pore volume above the pressure of about 100 atm results only from the compressibility of coal substance; therefore no pores exist in the range of radius from several hundred to 75 A in coal substance.

TL;DR: In this article, the equilibrium moisture contents of various low-rank coals have been determined at a constant humidity and have been related to the carboxyl and phenolic hydroxyl contents.

TL;DR: In this paper, the tensile strength of industrial coke was determined using the diametrical compression test, the test specimens being obtained from half-oven-width lumps by drilling cores from a series of positions across the lumps.

TL;DR: In this article, it was observed that activation of coal to small B.O. can lead to the production of molecular sieves, and the activation energy of methane diffusion is small.

TL;DR: The presence of n-propyl and n-butyl groups in coals was demonstrated by treating coals with sodium hypohalite at 60 °C and measuring the yields of acetic and propionic acids as mentioned in this paper.

TL;DR: In this paper, the effect of desorption of moisture from coal was studied and the results showed that the rate of heat loss from coal due to this process was greater than that due to oxidation of the coal.

TL;DR: In this paper, the binary adsorption characteristics of dry coal to 40 atm pressure have been calculated from pure-component isotherms, and the gas nonideality was accounted for by replacing pressure with fugacity.

TL;DR: In this paper, the authors show that the maximum reflectivity of coalified anthracites tends to be higher in sections parallel to the plane of the bedding than in sections perpendicular to it.

TL;DR: In this article, a series of cokes representative of the majority of foundry cokes produced in the United Kingdom was examined by the diametrical compression test to determine the tensile strength.

TL;DR: In this article, a bituminous coal was oxidized with 18 O 2 at 100 °C for 72 hours to simulate weathering, and subsequently pyrolysed at various temperatures to drive off C 18O 2, C 18 O 16 O, C 16 O 2, c 18 O, c 16 O O, H 2 18 O and H 2 16 O. These gases were subsequently analysed by mass spectrometry.

TL;DR: In this article, the densities of vitrains of twelve Japanese coals and five foreign coals were measured in methanol, n-hexane and mercury at 25 °C using a vacuum apparatus.

TL;DR: In this article, the basic nature of the underlying processes involved in the catalytic activation of coke by the addition of sodium carbonate to coal before carbonization was established, and the results lead to the conclusions that the presence of sodium carbomethane alters the course of the carbonization process and leads to the production of a coke which contains chemically-combined sodium and which is of similar structure to but different texture from coke produced in the absence of salt.

TL;DR: In this article, the extent of sulphur removal from seven U.S. coals has been studied by low-temperature oxidation, and the total sulphur in these coals varied between 3 and 7% by weight.

TL;DR: In this paper, the authors investigated the behavior of combustible fuel drops in a high-temperature flow field and found that the heat of decomposition and the total heat input to the drop per unit initial drop mass during the liquid phase are unaffected by airstream temperature and initial drop size in the range studied.

TL;DR: In this paper, a study has been made to determine whether blast-furnace cokes show similar behaviour to those of foundry cokes using the diametrical compression test and applying the Weibull statistical theory of strength.

TL;DR: Adsorption of titanium on humic acids, peat and coal macerals has been studied at pH values ranging from 0.8 to 2.0 in this paper.

TL;DR: In this article, magnetization measurements were applied to a coal char resulting from a liquefaction pilot unit study and the iron in the char was characterized as a mixture of Fe7S8 and FeS2 on the basis of thermomagnetic curves.

TL;DR: In this paper, the sulphur content of the parent coals ranged between 3.0 and 7.3% and that of the chars between 1.3 and 3.8% by weight.

TL;DR: In this paper, it is suggested that sodium/ash reactions within burning pulverized-fuel particles may result in a considerable reduction in the release of sodium to the furnace atmosphere and that the fine supercooled molten ash particles, enriched with alkali, may contribute to the initiation of diffusion-type primary deposits.

TL;DR: In this article, the compositions of the volatile products from Gray-King low-temperature carbonization assays of five coals are considered, with reference to their previous work showing the relations of the hydrocarbons and the oxygen-containing structures in coal to those in such products.

TL;DR: In this article, the same weakly-caking coal as was used in previous work in thin layers in nitrogen resulted in an evolution of hydrocarbons in two distinct stages.

TL;DR: In this article, high-resolution mass spectrometry was used to determine the organic species present in coal-carbonization products, airborne particulates, and municipal effluents.

TL;DR: In this paper, the rate data of the hydrocracking reaction of low-temperature tar are presented and the overall order of the reaction was found to be second order below 1500 psi and first at and above 1500 psi ∗.

TL;DR: In this article, the authors investigated the correlation between the silica/alumina ratios of coal seams and petrographic compositions and the relative frequency of dirt band occurrence in coal seams.