04462 Effect of coal drying on ammonia liquor and COG [coke-oven gas] purification process

01

97104451 upgrading

Restucturing of the Russian for power engineering

coal industry

and coal

Malyshev, Y. N. Izo. Akad. Nauk, Energ., 199h, (5), 3-10. (In Russian) The paper reports on coal deposits in Russia and technologies for coal upgrading. such as briquetting, liquefaction, and gasification.

Short history 97104452 on Varpalota, Hungary

of lignite

Jozsefne. H. Bu!rvu.sz. Kdmz. (In Hungarian)

Derived 97104453 petroleum

Lapok,

mining

Bauyaw.,

and Palota fortress 1996,

129, (5), 508-S 12.

Solid Fuels

Apparatus products

for

production

of fuels

from

waste

Kohayashi, S. Jpn. Kokai Tokkyo Koho JP 09,229,322 [97,229,322] (Cl. F23GS/O27), 5 Sep 1997, Appl. 96161,596, 2ti Feh 1996, I3 pp. (In Japanese) This apparatus comprises a combustion furnace, with a melting furnace, preferably airtight, placed within it for melting waste petroleum products. This is achieved using heat from the combustion furnace, preventing the combustion of the waste petroleum products. It also contains a part for supplying the waste petroleum products to the melting furnace from out of the combustion furnace and a part for producing fuels from the melted waste petroleum products. Alternatively, the apparatus consists of a combustion furnace and a part having melting cells for transporting the waste petroleum products through the combustion furnace, preventing the combustion of the waste petroleum products, and melting them in the cells by heat from the combustion furnace to produce fuels. The apparatus is both compact and economical and it produces lumps of fuel of moderate size with good handleability. 97104454

Assessment

of coking plant wastes as additives

Barriocanal, C. PI al. DCMK Tagwrgsher., 1997, 9703, (Proceedings ICCS ‘Y7, Volume 2) 677-0X0. In-.rirrr additives for coke making can be obtained from waste materials derived from coking plants. The effectiveness of such materials in the plastic coal range was compared with a coal-tar and derived pitches of different applications. Thermal analysis parameters of the additives were related to the extent of the modification of the Gieseler maximum fluidity of coking coal additives mixtures. Induced changes in plastic range modify the development of coke anisotropy and the honding between coke matrix and inert material, consequently improving coke properties.

97104455 Carbonization of wet and preheated coal. Effect on coke quality and its relation with textural properties Alvarez. R. et al. J. Analysis Appl. pYro/y.~is, 1996, 38. il9-130. In comparison with the conventional wet charging system using a Spanish high-volatile bituminous coal, the effects of coal preheating on the quality, textural and surface properties of the coke were assessed. Coal was flash dried and preheated in a 2 t h-’ precarbon pilot plant. Carbonization tests on the wet and preheated coals were carried out in a semi-industrial scale oven of h tonne capacity. Because textural and surface properties have an important effect on coke quality, an exhaustive characterization of the resultant cokes was made. Cokes were characterized by using microscopic image analysis. mercury porosimetry, density measurements, optical and SEM of surfaces. Mechanical strength and reactivity towards CO2 were also studied. Surface areas were determined by N? adsorption at 77 K using the Bruoauer-Emmett-Teller (BET) equation and CO: adsorption at 273 K using the Duhinin-Radushkevich (DR) equation. The results showed that coal preheating improved coke mechanical strength considerably. but at the same time increased the reactivity of the cokes. Increased microporosity and CO? surface area could account for the higher reactivity. 97104456 Coal heating apparatus using microwave Shudai, K. and Igawa. K. Jpn. Kokai Tokkyo Koho JP 09,176,656 [97,176,656] (Cl. ClOBS7/OX). 8 Jul 1997, Appl. 951341.599, 27 Dee 1995. h pp. (In Japanese) Apparatus for coal heating using microwave in the manufacture of metallurgical or blast-furnace coke is described. It comprises a closed box-shaped metal vessel with a microwave-introducing tube for directing microwave having 915-2450 MHz frequency through an irradiating opening connected with the first wall of the heating vessel. and a dividing plate inside the heating vessel for separating the vessel space into an irradiation space. A coal filling chamber is also separated by the dividing plate.

Coke degradation

charging technology to restrain the coke degradation were introduced. In addition, optimum operation of BF with maximum coal injection rate was discussed.

97104456 Influence

Coke strength development in the coke of maximum temperature and heating rate

oven.

1.

Amamato, K. Fuel. 1997. 76, (1). 17-21. The paper investigates the mechanism of coke strength development in coking of a conventional coal blend to find the preferred heating pattern for the production of coke of homogeneous quality. Relations of some coke properties to maximum coke temperature (MCT) or heating rate were explored. Both drum strength indexes DIil?’ and DIIT”’ of the coke increased with increasing MCT but decreased with increasing heating rate. After reaction with CO: (CSR), the coke strength index varied widely with the position of the sample in the direction of the oven width. Although the CSR for a particular zone in the chamber tended to increase with increasing heating rate in the zone. the heating rate in another zone also strongly influenced the CSR. Such influences of the heating rates are discussed in relation to mass transfer among the zones and the coking volume of the respectively zone. Based on the results, some means are proposed for producing cokes with more homogeneous strength in the oven.

97104459 Correlation of coke properties, and carbon consumption

anode

properties,

Leach, C. T. et al. Li$t Me/., 1997, 4X1-488. A comparison between laboratory analysis data and production data from 1992 through 1995 at RMC’s Lake Charles Carbon Company (LCCC) and Canadian Reynolds Metals Company (CRMC). During this period. carbon plant operations produced anodes with a range of properties using various calcined cokes. The results indicate that calcincd cokes having a range of properties can produce quality pre-bake anodes that yield low, stable carbon consumption. Little or no detrimental effect on carbon consumption was caused by variability in certain coke and anode properties that are considered important quality parameters. Limited correlation exists between certain coke and anode properties during time periods where the coke property changed significantly.

for

coke-making

97104457

So/id fuels (derived so/id fuels)

in blast furnace with high rate of

coal injection Li, J. and Mi, K. Yiqqwng Kexue Xuehuo.. 1997, 15, (1). X9-95. (In Chinese). The paper studies the correlation of the packed coke in a blast furnace (BF) with the injection of coal. The effect of coke quality, gasification reaction, in-.\i/ll reduction. and coke-melt reaction on the coke heat strength is considered. Methods of increasing the ore permeability and using new

97104460 Creep analysis during coal carbonization

of lump coke deformation

behaviour

Sam, H. er al. Fnel. 1997. 76, (4), 31 I-319. In order to estimate the coal carbonization process within a coke oven chamber. a thermal stress analysis model has been developed. It includes the effect of viscoelasticity of the plastic and semi-coke layers. dilatation of the plastic layer and the dependence of the thermophysical properties on the extent of the pyrolytic reaction. An experimental study was also carried out to measure the coke displacement and to observe the coke deformation behaviour in a laboratory-scale coke oven at various heating rates. The displacement calculated with the thermophysical properties which depend on the extent of the pyrolysis reaction gives better agreement with experimental data than with those dependent on temperature, as the heating rate increases. The effect of heating history is therefore an essential factor in the thermophysical characteristics of lump coke. Good agreement between displacement estimated hy the viscoelastic model and experimental results was observed, compared with that estimated by the elastic model. Thus, the viscoelasticity has to be considered for accurate estimation of the coke deformation behaviour. The estimated maximum principal stress within the lump coke under the constraint of the upper wall of the oven is larger than that under the free dilatation condition, in agreement with experimental observation.

97104461 Development and evaluation refuse-derived fuel (RDF) pellets

of

lime

enhanced

Ohlsson, 0. 0. Solid Wasre Mannge.; Therm. Tmr. Wtrsrc-m-f%er~ Technol., Proc. /,tt. Spec. Cor$, 1995, (Pub. 19Y6). 124-134. The production of two general types of refuse-derived fuel (RDF) products is discussed: a fluff type RDF which has a low bulk density-2-4 Ibift’; and densified RDF (d-RDF) produced by further processing fluff RDF into a densified fuel product. To produce d-RDF, fluff material is extruded under pressure to create cylindrical pellets, typically 2-3 in. in length and S/X-3/4 in. in diameter. with a bulk density of 20-35 Ibift’ and an energy content of 6SlG7001) BTU/lb. To alleviate problems encountered with d-RDF as a feedstock, a multi-phase study was conducted to develop a low-cost binder to improve d-RDF pellet quality. Chemical and physical tests indicated lime [Ca(OH)2] was the most effective hinding agent. In addition to the advantages lime provided as a physical binding agent. it was felt it also might prove beneficial in air quality emissions when co-comhusted with coal. Two combustion systems were tested: a spreader-stoker travclling grate system and a cyclone-fired system. Pollutants released during co-firing of d-RDF and coal were quantified.

97104462 [coke-oven

Effect of coal drying on ammonia gas] purification process RIST Ymgrr Nmnrm.

liquor and COG

1997, I I, (2). 264-270.

(In Kim, J. G. and Kim, J. Y. Korean) The paper provides details of predictive research for obtaining higher production rates of coke with coal drying. Overall. wastcwater flow rate will be increased, with an expected increase in pollutants emissions. In particular, HCN increases were observed at increased carbonization rates. Some calculations showed that COG purification efficiency will he

Fuel and Energy Abstracts

November

1997

387

01

Solid fuels (derived solid fuels)

maintained with the increased COG flow rate \chen more fresh washing water i\ used. With rcspcct to coal tar treatment. tar sludges were increased due to coal drying, and the amount of tar -‘as also incrrased. Tar treatment can hc Improved by increasing the ammonia liquor residcncc time in the tar decanter. 97104463 Estimation of thermal stress in lump coke Saw. H. et cl/. Fuel. 1097, 76. (4), 303-3 10. Lump coke maintains permeability in the blast furnace, governed hy the mean size and size distribution of the coke. Coke lump size is determined mainly by the growth of macro-cracks from the wall sidr to the centre of the coke oven charge. Their formation hehaviour depends on the property of thr coal charged and the operating conditions. In the formation process, micro-cracks arc simultaneously formed in all directions and their formation also play\ a part in determining the strength and therefore the lump size of coke for the blast furnace. This study estimates the deformation behaviour of coke and the thermal stress distribution. This method assumes the size of lump coke formed in the coke oven (distance hetwccn macro-cracks) and the conditions required for fissure propagation. considering radiative heat transfer within the fissures. The tensile stress parallel to the own wall is estimated in reach - IO-20 MPa near the wall side. Estimation of the growth of fissuras arising from the wall side was successful.

97104464

Historical

aspects of the coking in Japan 1945-1965

Ishikawa, Y. Femniu, 1997. 2. (7), SIS-526. (In Japanese) A review is provided of coking plants after World War II, change in the coal quality. coal pre-treatment, combination of coals in coking, coking furnaces. coke productivity and quality, and by-products recovery.

Hydrogenation and carbonization using organometallic complexes

97104465

of coal tar pitch

Ishihara, A. et ul. DGMK Tugw~g~her.. 1997. 9703, (Proceedings ICCS ‘97, Volume 2), 665-668. A higher activity was found in metal particles derived from Ruj(CO),? and Mo(CO)h than those from the supported catalyst and other metal complexes for the hydrogen addition and exchange reactions from gas phase in pitch. The yields of HS, HIS-BS, and BIS-THFS fractions increased by the use of metal carbonyls. which also inhibited the hydrocracking of pitch to gas and liquid fractions. In the carbonization of the hydrotreated coal tar pitch with and without fine molybdenum and ruthenium particles, the molybdenum and ruthenium particles selectively promoted the condensation of the lower molecule hydrocarbons. The carbonization yield of coal tar pitch and the hydrogen content of resultant cokes when Mo and Ru were present were greater than when metal particles were absent. 97104466

prepared

Kinetic study of CO2 gasification from British coal

of maceral

chars

Zhao, W. et al. Meirrrn Zhwnl~uu, 1996. IY, (4), 50-55. (In Chinese) A study was conducted on three maceral groups (vitrinite, fusinite and exinite) from British coal and their gasification kinetics in CO2 by TGA (thermogravimetric analysis) at the pressure of 0.1 MP. 97104467

hydrocracking

Kinetics of asphaltene of a coal residue

hydroconversion.

1. Thermal

Martinez, M. T. PI a/. Furl, 1997, 76. (IO), X99%905. A synthetic crude obtained by direct liquefaction of a Spanish subbituminous coal was deasphalted and the resultant asphaltene-rich residue was submitted tu several upgrading routes. The results from thermal hydroprocessing arc reported. Solubility-hased lumped kinetics with parallel reactions for oils. gases and coke formation are proposed. Conversion data fit second-order kinetics for asphaltene conversion and for oil, gas and coke formation. Coke formation was inhibited except under the harshest reaction conditions. Two types of coke formation are proposed: one as primary reaction product after an induction period and the other as secondary product from a sequence of polymerization steps. If hydrogen is present, primary coke formation is strongly inhibited. Structural analyses show higher aromaticity of the oils from products ohtained at 475°C than at 4SO”C, which supports the proposed condensation mechanism for coke production at high temperatures 97104468

manufacturing

Manufacture of fuel units facility and its apparatus

in refuse-derived

fuel

Kaminaga, K. et al. Jpn. Kokai Tokkyo Koho JP 09,235,576 (97,235.576] (Cl. ClOL5146). 9, Sep 1997, Appl. 96/63,X62, 27 Feb 1996, 6 pp. (In Japanese) The manufacture of highly compacted fuel units takes place in a refusederived fuel manufacturing facility. Collected wastes are solidified into a prescribed size while removing foreign matter-mixed units. The solidified units are dried as required and then accumulated. The units compacted due to their own weight in the accumulated bottom part are pushed out in the transverse direction. Apparatus for the manufacture comprises a collecting part to house the wastes, a means to transport the wastes successively from the collecting part, a hammer mill type means in solidify the waste into the unit size, a second means to transport the waste units and remove foreign matter-mixed units, a part to accumulate the transported units successively from an upper side, and a pressing and pushing out means to push out transversely the accumulated units in the bottom to a transportation

388

Fuel and Energy Abstracts

November

1997

container. The fuel units are then transported to a combustion part TV,hc burned. The fuel units arc made in have high hulk density at low cwt. resulting in decrease of transportation cost. Metal haste\ are separated resulting in prevention of corrosive gas cvolutwn and clinker formaticrn.

97104469 Manufacture of solid fuels-water slurries for gasification Sawad~~.M. ef (11. Jpn. Kokai Tokkyo Koho JP 09 03.464 [U7 03.4641 (Cl. CIOLl!32). 7 Jan l9Y7. Appl. YS:lS3.029, 20 Jun IYYS. 7 pp. (In Japanese) This process rccyclcs fine slags containing unrcactcd \r,lid fuels. ohtalnctl by partial oxidation of petroleum c[,kes and coals. It compriws grinding of slurries containing IO-40 wt? fine +g\ hy preliminary wet grinders followed hy mixing with solid fuel\ and grlnding by primary grinders to give geometrical average diameter 30-125 ,rm. Rcwlting \Iurric\ have hlph concentration and gasification efficiency.

97104470 Mathematical simulation for delayed coking furnace. II. Mathematical model of coking furnace Pan, H. er ol. Shiyou Xwhuo, Shiymr JinRmg. l’J97. 13. (2). 2Y-33. (In Chinese) ‘The paper describes a mathematical model of a coking furnace, which take\ into account the reaction and coking in the tuhe and recirculation for flue gas. Heat transfer and pressure drop arc calculated by homogcncous model of two-phase tlow. The Roesler model i\ applied to burning calculnti~,n.

97104471 Method and apparatus ening-melting property of coal

for determination

of soft-

Fukada, K. cf N/. Jpn. Kokai Tokkyo Koho JP 09.IXJ.XIS [cJ7,1XJ.XlS] (CI. GOlN2.5/04). IS Jul 1997. Appl. YS!353.(145. 28 Dee 1005. 8 pp. (In Japanese) The softening-melting property of coal in coke manutacturc hy rapid pyrolysis can be determined via the following method. A coal sample i\ filled in a crucible equipped with a stirring rod and hcatcd with the stirring by the rod having a fixed-torque rotation speed under an Inert gas atmosphere and at IO-10,00O’C/min heating rate. The rotation \pcccl i\ determined and the data of rotation speed and temperature data of the coal sample is combined for data proce\cing. The softening-melting prl,prrty i\ calculated from the results of data processing.

97104472 Method for producing solid and porous lignite fuels with improved combustion properties Naundorf. W. et al. Ger. Offen. DE lY,hOX,3X6 (Cl. CIOL.5;04). I I Scp 1997.. Appl. l9,hO8,3X6. 5 Mar I9Yh. 3 pp. (In German) Fibrous xylite is removed from lignite by mechanical procc\\ins. Each IS processed separately by comminution and classification tn a spc~ifircl size (e.g., xylite
97104473 New method for evaluation of blast-furnace high temperatures in a turbulent air stream Stuchlik. V. With regard the Sahels examined at

coke at

and Frydl. Z. Hwl. Lisv, IYYh, 51, (12), X-l I. (In Czech) to the evaluation of metallurgical coke quality, the suitability of method was assessed. Strength and wear resistance were 1000-1700’ C to simulate blast furnace conditions.

97104474 of extreme

Novel silica material in a hardness test-simulation compressive loading in a technical institution Surman, E. el al. Comm. Eur. Commmities, /Rep./ EUR. I99fi. (EUR 15235), 139 pp. The semi-technical coke oven built with high-thermal conductive-typr silica bricks underwent a test program comprised of long-term coking tests with three different coal blends run each at 1150. 1250. 1350 and 145OC. This test program was performed gradually under the following vertical load\ of the wall bonds: 0.3. 1 and 2 N/mm’. Then the vertical wall load was reduced to the starting value of 0.3 N/mm’ and by a variation in the coal hlend composition, a different horizontal load on the wall hond hy wall pressure, was caused with the objective to strain the wall hond possibly up to it\ destruction to determine its limit load hearing capacity in this way. Coking times up to 2 h shorter than those of a conventional coke oven. a performance increase of about IO%, could he reached in the perftjrmed long-term tests.

97104475 Oil-slurry dewatering of Victorian brown coal. Its effects on the coal structure and reactivity for low temperature oxidation Okuma, 0. cl al. DGMK Tag~rr&w., 1997. 9702. (Proceedings ICCS ‘Y7. Volume I), 491-494. The UBC process was used tn upgrade Victorian brown coal to solid fuel with a higher heating value. In the UBC process, the coal is dewatercd in a petroleum-derived oil which is recovered after de*atcring hy centrifuging and vaporization. The reactivity of this upgraded coal (UBC) for Iow temperature oxidation is reduced by its structural change during dewatrrin&. With asphalt-containing oil, the coal-oil slurry was stabilizrd. and the oxidation reactivity of UBC further decreased.