[en] Short communication. 2 refs, 1 fig., 1 tab

[en] Present article is devoted to organo mineral wastes of coal development and processing as a complex energy raw material. The technical conditions on using of ash slag products as fuel for application in various types of furnace plants depending on their humidity, ash content and sulphur content was elaborated.

[en] In this study, the effect of extractive content on fuel properties of selected woody and non-woody biomass samples has been evaluated. The results show significant variation in the amount of extractives (15-70%) present in different biomass samples. There is significant decrease in ash content, fixed carbon content and calorific value in extractive-free samples. The elemental carbon reduces after extraction in woody biomass. There is no specific trend observed in the reduction of elemental carbon with removal of extractives in non woody samples. In extractive-free samples, ash content decreases by 2-60%, fixed carbon content by 7-24% and calorific value by 1-17%. In conclusion, fuel properties of unextracted biomass are found to be better than extracted biomass. (author)

[en] Estonian oil shale ash contains chemically active compounds which would undergo different spontaneous transformations in the atmosphere of air. For explaining these processes the system ash-water-air was studied storing moisture samples of ash in laboratory in open-air as well as hermetic conditions. The samples of dry ash formed at pulverized combustion of oil shale at the Baltic Power Plant, and samples obtained from ash storing plateau from different depth of different boreholes were under investigation. Storing conditions as well as the properties of initial samples have a great influence upon the processes taking place at storing of ashes. The results obtained could be used to explain and control the processes taking place at storing of ashes under atmospheric (wet) conditions

[en] In this paper, the results of the Spherical Oil Agglomeration of .45 micrometer super pits low grade coal particles (Bag worth Colliery, U.K.) within a suspension are presented. Demineralized agglomerates were recovered directly by sieving on a 106 micrometer sieve. Very good reductions in the ash content of the feed coal samples were achieved. In order to reduce the high levels of the crude oil dosage comparatively, small quantities of surfactants were added to the suspension. Of the various surfactants screened, Triton x.405 (non.ionic) proved to be very efficient and a crude oil reduction of over 60 weight % was achieved for concentrates containing 8 weight % ash

[en] Highlights: → Chemical energy values are 2.16-5.20 times as the physical energy values. → Chemical exergy values are 4.50-13.45 times as the physical exergy values. → Efficiencies mainly increase first and then decline when ER/temperature increases. → Higher carbon and hydrogen content generates higher energy and exergy values. → Higher ash content results in lower energy and exergy values/efficiencies. - Abstract: Biomass gasification with air in autothermal gasifiers is studied and compared with another fuel from thermodynamic aspect. The results indicate that the chemical energy values of product gases from biomass are 2.16-5.20 times as the corresponding physical energy values, while the chemical exergy values are 4.50-13.45 times as the corresponding physical exergy values. The energy and exergy efficiencies of biomass gasification are respectively in ranges of 52.38-77.41% and 36.5-50.19%, and mainly increase first and then decline when ER or gasification temperature increases. Higher carbon and hydrogen content in the ultimate analysis generates higher gaseous energy and exergy values, while results in lower energy and exergy efficiencies. Higher ash content makes biomass produce lower energy and exergy values/efficiencies.

[en] A stockpile probe based on backscattered gamma-gamma-ray technique was tested for the determination of coal ash. A centralized tool employing a gamma-ray source of very low radioactivity (1.85 MBq) was used. This logging tool was tested using ¹³⁷Cs and ¹³³Ba sources with a 37 mm (diameter) by 75 mm NaI (TI) scintillation detector. Ten source-detector configurations were analyzed using ¹³⁷Cs , and another nine source-detector configurations are analyzed, using ¹³³Ba source, both for four geophysical models, having a borehole diameter of 90 mm. Regression analysis on the laboratory logging data for each studied configuration was carried out in order to establish calibration equations for ash prediction. The optimum configuration for the logging stockpile probe using ¹³⁷Cs source was determined to be 80 mm source to detector spacing, and 80 mm iron thickness shielding. This configuration gives the best results for ash prediction. The root mean square (rms) deviation for ash is 1.52%. The optimum configuration for the logging stockpile probe using ¹³³Ba source is determined to be 85 mm source to detector spacing, and 50 mm iron thickness shielding. This configuration gives the best results for ash prediction, where the rms deviation for ash is 1.47%

[en] This work presents the results of a study of raw materials and light-weight concrete properties and study of radionuclides concentrations in raw materials and light-weight concrete and their radiological implication. Furnace bottom ash from Israeli thermal power stations is a potentials material to be used as an aggregate in light-weight concretes.Utilization of furnace bottom ash wastes, can offer a solution to persistent ecological problems related to Use disposal of the ash as well as an economic Solution fur building materials production. The technical specification of the furnace bottom ash is close to the grading of natural sand and crushed stone, but with a high porosity and low density. (authors)

[en] A stockpile probe based on backscattered gamma-gamma-ray technique was tested for the determination of coal ash. A centralized tool employing a gamma-ray source of very low radioactivity (1.85 MBq) was used. This logging tool was tested using ¹³⁷Cs and ¹³³Ba sources with a 37 mm (diameter) by 75 mm NaI (TI) scintillation detector. Ten source-detector configurations were analyzed using ¹³⁷Cs, and another nine source-detector configurations are analyzed, using ¹³³Ba source, both for four geophysical models, having a borehole diameter of 90 mm. Regression analysis on the laboratory logging data for each studied configuration was carried out in order to establish calibration equations for ash prediction. The optimum configuration for the logging stockpile probe using ¹³⁷Cs source was determined to be 80 mm source to detector spacing, and 80 mm iron thickness shielding. This configuration gives the best results for ash prediction. The root mean square (rms) deviation for ash is 1.52%. The optimum configuration for the logging stockpile probe using ¹³³Ba source is determined to be 85 mm source to detector spacing, and 50 mm iron thickness shielding. This configuration gives the best results for ash prediction, where the rms deviation for ash is 1.47%

[en] Pakistan has got huge deposits of lignite coal which remains unexploited due to high ash and sulphur contents. Pakistan Mineral Development Corporation (PMDC), and Lakhra Coal Development Company (LCDC), supplied coal samples from their coal mines at Lakhra for analysis and testing. These air dried samples of lignite coal were crushed, ground and subjected to initial analysis and 'Float and Sink' tests. The coal was found to contain moisture 9.04%, volatile matter = 33.52%, ash 26.7% and sulphur = 5.4%. Float and sink tests were conducted on plus 20 mesh fraction of Head sample, in Zinc chloride solution of specific gravities 1.4, 1.5, 1.6 and 1.7. The ash contents in float and sink fractions of each test and sulphur contents in float and sink fractions of three tests were determined. The data obtained was used to construct washability curves on ash and sulphur basis. The washability curves indicate that at an assumed 15% ash level, the recovery of clean coal is 70% with a reduction in total sulphur content of clean coal from 5.42% to 3.20%. (author)