To explore the chemical of hydrous pyrolysis and processes of primary migration, Bakken Shale with a content of 17% on total organic matter, was heated under water at temperatures of 25-300 ° for 2 h. The organic matter, a mixture of oil and bitumen, was liberated from the rock starting at 275 ° and at 300 ° the release of the organic matter was complete. The release of Cb C2 and CO,,. indicated that some chemical reactions occurred, but the rapid release of the organic matter from the rock was due to a physical process, probably the glass-to-rubber phase transition of the kerogen. The achieved data suggested that the oil in Bakken Shale was diffusionally trapped and required a change of state of kerogen for its release.

03•00470 Underground damages caused by opencast coal mine blasting Singh, P. K. et al. Glueckauf, 2002, 138, (3), 91-97. A study was conducted to investigate the damage to underground openings caused due to vibration generated by opencast coal mine blasting. The objective was to suggest optimal blast design to avert such damage. Altogether 37 blasts with varying charging pattern and initiation system were conducted at Samleshawari opencast mine and 108 blast vibration data were recorded at Hingir Rampur colliery in India. The strata monitoring instruments were installed in the under- ground mine to monitor the strata behaviour. The analyses of vibration data indicate that the roof of the underground openings vibrated with higher amplitude of vibration compared to pillars. Deterioration in pillars, roof and ventilation stoppings were observed. Strata monitoring studies indicated some amount of divergence between roof and floor, just after blasting but, later on it was followed by convergence and most of the divergence that occurred was restored. The study was continued for 9 months but it did not indicate any abnormal change in strata behaviour. Based on the analysis of data, propagation equations were established to compute the safe explosive weight per delay to be detonated in opencast mine for safety of underground workings.

Preparation

03•00471 Cleaning of Egyptian coal by using column flotation to minimize the environmental pollution Abdel Khalek, M. A. Afinidad, 2002, 59, (497). 34-38. This work aims to decrease the sulfur content of the Egyptian coal so as to be suitable for various applications by using column flotation technology. The column flotation parameters of air flow-rate, wash water, frother dosage, slurry feed rate and its solids percent were studied. A clean coal was obtained containing 1.01% total sulfur with a yield of 82%, from Maghara coal (Sinai-Egypt) which contains 2.2% total sulfur as raw coal.

03•00472 Coprocessing of Yanzhou coal with a FCC slurry Wang, Z. J. et al. Preprinls o f ,~vmposia American Chemical Society, Division o/" Fuel ChcmistD', 2002, 47, (1), 192-193. Coal samples obtained from Yanzhou, China, were coprocessed using a fluid catalytic cracking (FCC) slurry under different reaction con- ditions. Coprocessing experiments were performed under the following conditions: Nz atmosphere with catalyst; N2 atmosphere without catalyst; and He atmosphere with a ferrous sulfate-based catalyst impregnated on coal. To understand the interaction between coal and slurry, the Yanzhou coal was coprocessed with the FCC slurry at two different coal/slurry ratios under the reaction conditions mentioned. Results show that the addition of FCC slurry greatly enhanced coal conversion, which is attributed to its good H-shuttling capacity and dissolution ability for coal radicals. The T conversion decreased when more FCC slurry was used in the coprocessing, while excessive FCC slurry may hamper further cracking of preasphaltene by stabilizing coal radicals. In the presence of N2, coal and FCC slurry have a synergistic effect on the production of oil and <220°C fraction in coprocessing. In the presence of He and catalyst, polyaromatics of FCC slurry may be converted into hydroaromatics, which enhances H-donor ability and promotes the cleavage of strong bond of coal structure.

03•00473 Deep suppression of NOx during staged combustion of Kuznetsk coal with U-shaped flow through- vortex torch Vagner, A. A. el al. Teploenergetika. 2002. (2), 14 19. (In Russian) An efficient staged combustion of Kuznetsk coal with suppression of nitrogen oxides obtained after retrofitting of a thermal power plant boiler was described.

03•00474 Impact of the particle sizes of the pulverized-coal on desulfurization by microwave radiation Cheng, R. Huazhong Keji Daxue Xuehao, Ziran Ke.\uehan, 2002.30, ( 11. 93 95. (In Chinese)

01 Solid fuels (preparation)

The effect of coal desulfurization by microwave radiation on the pulverized-coal sample of different particle sizes with Moessbauer Spectroscopy is presented. The result indicates that the smaller the size of the particle, the greater the transformation of pyrite to pyrrhotite will be, and the better effect will be that of the desulfurization. The complete transformation of pyrite to phyrrhotites occurs in the sample with the smallest particle size and the rate of therm~il-desulfurization reactivity is very high.

03/00475 Influence of gaseous additives on desulfurization of Yanzhou coal through pyrolysis Xu, L. et al. Ranliao Huaxue Xuebao, 2002, 30, (2), 175-177. (In Chinese) Development of sulfur removal processes from coal prior combustion may play an important role in use of high sulfur coals. Pyrolysis transforms a portion of sulfur in coal to the gas and liquid phases, and it may be possible to generate low sulfur chars for clean combustion in boilers. This paper presents recent results on the influence of gaseous additives on suffur removal from Yanzhou high sulfur coal. The experiments were conducted in a fixed-bed reactor with a heating rate of 10%. Nitrogen, organic reagents (ethanol and acetone) and water were used to constitute different atmospheres. It was observed that introduction of the organic reagents in pyrolysis promotes sulfur removal, which results in obvious decrease in sulfur content of char. Under the conditions studied, addition of ethanol is most effective for desulfurization of the coal.

03•00476 Microbial desulfurization of solubilized coal Back, K. et al. Bio-technology Letters. 2002, 24, (5), 4014.05. Microbial desulfurization of low rank sub-bituminous and lignite coal by Rhodococcus rhodochrous IGTS8 was studied using three different pretreated coal samples. Solubilized coal was desulfurized more efficiently than hard coal and more sulfur was extracted from biologically solubilized coal than from chemically solubilized coal. Microbial desulfurization combined with biological solubilization removed 75% of the total sulfur while the microbial desulfurization combined with chemical solubilization removed 63%.

03•00477 Migrating behaviour and mechanism of deleterious elements in Taixi coals during cleaning process Qin, Y. et al. Ranliao Huaxue Xuebao. 2002, 30, (2), 147-150. (in Chinese) Based upon the systematic analyses of the 19 elements in Taixi coal and its cleaned samples, the migrating behaviours during the cleaning process were detected and the migrating mechanism was discussed. The results showed that: (1) the trace deleterious elements As, Sb, Se, Co, Sb, Mo, Pb and Br are obviously enriched in Taixi raw coal samples, but most of them could be removed by washing; (2) the cleaning ability of the cleaned large-grade coal is the best which makes it the most favourable to the environment; (3) most of the deleterious elements might be enriched in the coal slime after washing so that the slime is not feasible to be used as fuel; (4) the migrating behaviours of the deleterious elements in coals could be derived from the integrative effect of some factors such as the element occurrence, maceral type and content and mineral structure in coals.

03•00478 Research on coal flotation by joined action of reagents and ultrasonic wave treatment Hu, J. e /a l . Zhongguo Kuangye Daxue Xuebao, 2002, 31, (2), 186-189. (In Chinese) Coal flotation experiments were performed with reagents and ultra- sonic wave treatment. The result shows that the dosage of BET, a flotation reagent, is less than the commonly used reagents GF and FS202, only 1/10 to 1/100 of the two reagents. In addition, the BET is good in selectivity and poor in collectivity for pyrite. In pyrite, the floated matter using BET is 1/10 to 1/20 of that by using GF and FS202. The ultrasonic treatment may further improve the restraint effect and increase its desulfurization ratio by 15%. The Jiexiu coal, for example, has a desulfurization ratio of 85%. By using CaO and water glass simultaneously, it may also improve the desulfurization effect.

03/00479 Residual moisture reduction in coarse coal centrifuges. 4. Theory, process engineering and costs Benito, R. el al. Minerals Engineering, 2002, 15, (4), 245-252. Air purging is a new way of reducing the moisture content of coarse coaI (i.e. within the 50-0.5 mm size range) products from vibrating basket centrifuges. The process, which involves injecting a turbulent stream of high velocity air through the coal bed as it traverses the centrifuge basket, has recently been shown to work at a commerical scale. This paper describes some background modelling and exper- imental work that was undertaken to enhance understanding of the technique. The most critical variables affecting air purging are the speed of the air exiting the bed and the height of the bed itself. Both parameters were characterized at commercial scale through a combination of experimental tests and modelling. These data were

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